2. Altibase Properties#

Altibase server can be run in various modes. The altibase.properties file is used to set Altibase server environment settings. The altibase.properties file contains all elements related to the operation and adjustment of the Altibase server.

This chapter describes the Altibase properties that need to be set and managed to configure and operate Altibase as a database suitable for the user's purposes.

Configuration#

There are three ways to set Altibase server environment settings.

The first method involves making changes to the Altibase properties file, which is located at $ALTIBASE_HOME/conf/altibase.properties. Because this method of configuration is static, meaning that changes can only be made while Altibase is not running, the Altibase instance must be restarted in order for the changes to the properties file to take effect.

The second method is dynamic, meaning that configuration changes can be made even while Altibase server is running. Although this method confers the advantage of being able to make and apply changes without shutting down the server, it is not possible for all properties. For properties that can be dynamically changed, the ALTER SYSTEM or ALTER SESSION statements can be used to apply the configuration changes to the entire Altibase server or to individual sessions, respectively.

The third method of configuring the Altibase environment is through the use of operating system environment variables. Like the method involving the altibase.properties file, this configuration method is also static. Properties that are read-only or that can only have a single value can be set in this way. After specifying the environment variable as ALTIBASE_property_name, it will be necessary to reboot the database server in order to implement the changes.

Here is an example.

$ export ALTIBASE_DEFAULT_DATE_FORMAT=YYYY/MM/DD

The precedence of the property-setting methods is as follows:

Environment variable settings
altibase.properties file settings
Default system values

As can be seen in the following example, when properties are set, because environment variables take highest precedence, the value of DEFAULT_DATE_FORMAT in the altibase.properties file is ignored, and the value of the environment variable is used.

$ export ALTIBASE_DEFAULT_DATE_FORMAT=YYYY-MM-DD
DEFAULT_DATE_FORMAT=YYYY-MM-DD (altibase.properties)

Similarly, in the following example, NLS_USE in the altibase.properties file is ignored, and UTF-8, which is specified by the NLS_USE environment variable, is used, because environment variables have the highest priority.

$ export ALTIBASE_NLS_USE=UTF8
NLS_USE=KO16KSC5601 (altibase.properties)

Properties Overview#

The property file for configuring the Altibase server is called "altibase.properties" and is located in the conf subdirectory of ALTIBASE_HOME. The properties therein are broadly grouped as follows:

Database initialization properties
Performance properties
Session properties
Transaction properties
Backup and recovery properties
Replication properties
Network and security properties
Message logging properties
Database link properties
Auditing properties
C/C++ external procedure agent properties
User account security properties
Other properties

The following table lists all Altibase properties. For reference, each group in the table has the following meaning:

D: Database initialization properties
P: Performance properties
S: Session properties
T: Transaction properties
B: Backup and recovery properties
R: Replication properties
NM: Network Management and security properties
M: Message logging properties
L: Database link properties
U: Auditing properties
A: C/C++ external procedure agent properties
AS: Account Security properties
E: Other properties

The values in the “Alter Level” column have the following meaning:

SESSION: the property can be changed using an ALTER SESSION statement.
SYSTEM: the property can be changed using an ALTER SYSTEM statement.
BOTH: the property can be changed using either an ALTER SESSION or an ALTER SYSTEM statement
NONE: Cannot be changed

Group	Class	Property Name	Alter Level
D		BUFFER_AREA_CHUNK_SIZE
		BUFFER_AREA_SIZE	SYSTEM
		BUFFER_CHECKPOINT_LIST_CNT
		BUFFER_FLUSHER_CNT
		BUFFER_FLUSH_LIST_CNT
		BUFFER_HASH_BUCKET_DENSITY
		BUFFER_HASH_CHAIN_LATCH_DENSITY
		BUFFER_LRU_LIST_CNT
		BUFFER_PREPARE_LIST_CNT
		COMPRESSION_RESOURCE_GC_SECOND
		DB_NAME
		DDL_SUPPLEMENTAL_LOG_ENABLE	SYSTEM
		DEFAULT_DISK_DB_DIR
		DEFAULT_MEM_DB_FILE_SIZE
		DEFAULT_SEGMENT_MANAGEMENT_TYPE
		DEFAULT_SEGMENT_STORAGE_INITEXTENTS
		DEFAULT_SEGMENT_STORAGE_MAXEXTENTS
		DEFAULT_SEGMENT_STORAGE_MINEXTENTS
		DEFAULT_SEGMENT_STORAGE_NEXTEXTENTS
		DIRECT_PATH_BUFFER_PAGE_COUNT	SYSTEM
		DISK_INDEX_UNBALANCED_SPLIT_RATE	SYSTEM
		DISK_LOB_COLUMN_IN_ROW_SIZE
		DISK_MAX_DB_SIZE
		DOUBLE_WRITE_DIRECTORY
		DOUBLE_WRITE_DIRECTORY_COUNT
		DRDB_FD_MAX_COUNT_PER_DATAFILE	SYSTEM
		EXPAND_CHUNK_PAGE_COUNT
		LOB_OBJECT_BUFFER_SIZE
		LOCK_MGR_CACHE_NODE
		LOCK_NODE_CACHE_COUNT
		LOGANCHOR_DIR
		LOG_DIR
		LOG_FILE_SIZE
		MAX_CLIENT
		MEM_DB_DIR
		MEM_MAX_DB_SIZE
		MEMORY_INDEX_BUILD_RUN_SIZE	SYSTEM
		MEMORY_INDEX_BUILD_VALUE_LENGTH_THRESHOLD	SYSTEM
		MEMORY_INDEX_UNBALANCED_SPLIT_RATE	SYSTEM
		MEMORY_LOB_COLUMN_IN_ROW_SIZE
		MEMORY_VARIABLE_COLUMN_IN_ROW_SIZE
		MEM_SIZE_CLASS_COUNT
		MIN_COMPRESSION_RESOURCE_COUNT
		MIN_LOG_RECORD_SIZE_FOR_COMPRESS	SYSTEM
		MIN_PAGES_ON_DB_FREE_LIST
		MIN_PAGES_ON_TABLE_FREE_LIST	SYSTEM
		MIN_TASK_COUNT_FOR_THREAD_LIVE	SYSTEM
		PCTFREE
		PCTUSED
		QP_MEMORY_CHUNK_SIZE
		RECYCLEBIN_DISK_MAX_SIZE	SYSTEM
		RECYCLEBIN_ENABLE	SESSION
		RECYCLEBIN_MEM_MAX_SIZE	SYSTEM
		REDUCE_TEMP_MEMORY_ENABLE	SYSTEM
		SECURITY_ECC_POLICY_NAME	SYSTEM
		SECURITY_MODULE_LIBRARY	SYSTEM
		SECURITY_MODULE_NAME	SYSTEM
		SERVICE_THREAD_INITIAL_LIFESPAN	SYSTEM
		SMALL_TABLE_THRESHOLD	SYSTEM
		ST_OBJECT_BUFFER_SIZE	BOTH
		SYS_DATA_FILE_INIT_SIZE
		SYS_DATA_FILE_MAX_SIZE
		SYS_DATA_FILE_NEXT_SIZE
		SYS_DATA_TBS_EXTENT_SIZE
SYS_TEMP_FILE_INIT_SIZE
SYS_TEMP_FILE_MAX_SIZE
SYS_TEMP_FILE_NEXT_SIZE
SYS_TEMP_TBS_EXTENT_SIZE
SYS_UNDO_FILE_INIT_SIZE
SYS_UNDO_FILE_MAX_SIZE
SYS_UNDO_FILE_NEXT_SIZE
SYS_UNDO_TBS_EXTENT_SIZE
TABLE_BACKUP_FILE_BUFFER_SIZE
TABLE_COMPACT_AT_SHUTDOW	SYSTEM
TEMP_HASH_BUCKET_DENSITY
TEMP_PAGE_CHUNK_COUNT
USER_DATA_FILE_INIT_SIZE
USER_DATA_FILE_MAX_SIZE
USER_DATA_FILE_NEXT_SIZE
USER_DATA_TBS_EXTENT_SIZE
USER_TEMP_FILE_INIT_SIZE
USER_TEMP_FILE_MAX_SIZE
USER_TEMP_FILE_NEXT_SIZE
USER_TEMP_TBS_EXTENT_SIZE
VOLATILE_MAX_DB_SIZE
P		AGER_WAIT_MAXIMUM
		AGER_WAIT_MINIMUM
		BUFFER_VICTIM_SEARCH_INTERVAL	SYSTEM
		BUFFER_VICTIM_SEARCH_PCT	SYSTEM
		BULKIO_PAGE_COUNT_FOR_DIRECT_PATH_INSERT	SYSTEM
		CHECKPOINT_BULK_SYNC_PAGE_COUNT	SYSTEM
		CHECKPOINT_BULK_WRITE_PAGE_COUNT	SYSTEM
		CHECKPOINT_BULK_WRITE_SLEEP_SEC	SYSTEM
		CHECKPOINT_BULK_WRITE_SLEEP_USEC	SYSTEM
		CHECKPOINT_FLUSH_COUNT	SYSTEM
		CHECKPOINT_FLUSH_MAX_GAP	SYSTEM
		CHECKPOINT_FLUSH_MAX_WAIT_SEC	SYSTEM
		CM_BUFFER_MAX_PENDING_LIST
		CM_DISPATCHER_SOCK_POLL_TYPE
		DATABASE_IO_TYPE
		DATAFILE_WRITE_UNIT_SIZE	SYSTEM
		DB_FILE_MULTIPAGE_READ_COUNT	SYSTEM
		DEDICATED_THREAD_CHECK_INTERVAL
		DEDICATED_THREAD_INIT_COUNT
		DEDICATED_THREAD_MAX_COUNT
		DEDICATED_THREAD_MODE
		DEFAULT_FLUSHER_WAIT_SEC	SYSTEM
		DELAYED_FLUSH_LIST_PCT	SYSTEM
		DELAYED_FLUSH_PROTECTION_TIME_MSEC	SYSTEM
		DIRECT_IO_ENABLED
		DISK_INDEX_BUILD_MERGE_PAGE_COUNT	SYSTEM
		EXECUTE_STMT_MEMORY_MAXIMUM	SYSTEM
		EXECUTOR_FAST_SIMPLE_QUERY
		FAST_START_IO_TARGET	SYSTEM
		FAST_START_LOGFILE_TARGET	SYSTEM
		FAST_UNLOCK_LOG_ALLOC_MUTEX
		HASH_AREA_SIZE	SYSTEM
		HASH_JOIN_MEM_TEMP_AUTO_BUCKET_COUNT_DISABLE	SYSTEM
		HASH_JOIN_MEM_TEMP_PARTITIONING_DISABLE	SYSTEM
		HIGH_FLUSH_PCT	SYSTEM
		HOT_LIST_PCT	SYSTEM
		HOT_TOUCH_CNT	SYSTEM
		INDEX_BUILD_THREAD_COUNT	SYSTEM
		INDEX_INITRANS
		INDEX_MAXTRANS
		LFG_GROUP_COMMIT_INTERVAL_USEC
		LFG_GROUP_COMMIT_RETRY_USEC
		LFG_GROUP_COMMIT_UPDATE_TX_COUNT
		LOB_CACHE_THRESHOLD	BOTH
		LOCK_ESCALATION_MEMORY_SIZE	SYSTEM
		LOG_CREATE_METHOD
		LOG_IO_TYPE
		LOW_FLUSH_PCT	SYSTEM
		LOW_PREPARE_PCT	SYSTEM
		MATHEMATICS_TEMP_MEMORY_MAXIMUM	SYSTEM
		MAX_FLUSHER_WAIT_SEC	SYSTEM
		MEM_INDEX_KEY_REDISTRIBUTION	SYSTEM
		MEM_INDEX_KEY_REDISTRIBUTION_STANDARD_RATE	SYSTEM
		MULTIPLEXING_CHECK_INTERVAL	SYSTEM
		MULTIPLEXING_MAX_THREAD_COUNT	SYSTEM
		MULTIPLEXING_THREAD_COUNT
		NORMALFORM_MAXIMUM	BOTH
		OPTIMIZER_AUTO_STATS	BOTH
		OPTIMIZER_DELAYED_EXECUTION	SESSION
		OPTIMIZER_FEATURE_ENABLE	SYSTEM
		OPTIMIZER_MODE	BOTH
		OPTIMIZER_PERFORMANCE_VIEW
		OPTIMIZER_UNNEST_AGGREGATION_SUBQUERY	SYSTEM
		OPTIMIZER_UNNEST_COMPLEX_SUBQUERY	SYSTEM
OPTIMIZER_UNNEST_SUBQUERY	SYSTEM
OUTER_JOIN_OPERATOR_TRANSFORM_ENABLE	SYSTEM
PARALLEL_LOAD_FACTOR
PARALLEL_QUERY_THREAD_MAX	SYSTEM
PARALLEL_QUERY_QUEUE_SIZE	SYSTEM
PREPARE_STMT_MEMORY_MAXIMUM	SYSTEM
QUERY_REWRITE_ENABLE	BOTH
REFINE_PAGE_COUNT
RESULT_CACHE_ENABLE	BOTH
RESULT_CACHE_MEMORY_MAXIMUM	SYSTEM
SECONDARY_BUFFER_ENABLE
SECONDARY_BUFFER_FILE_DIRECTORY
SECONDARY_BUFFER_FLUSHER_CNT
SECONDARY_BUFFER_SIZE
SECONDARY_BUFFER_TYPE
SORT_AREA_SIZE	SYSTEM
SQL_PLAN_CACHE_BUCKET_CNT
SQL_PLAN_CACHE_HOT_REGION_LRU_RATIO	SYSTEM
SQL_PLAN_CACHE_PREPARED_EXECUTION_CONTEXT_CNT	SYSTEM
SQL_PLAN_CACHE_SIZE	SYSTEM
STATEMENT_LIST_PARTIAL_SCAN_COUNT	SYSTEM
TABLE_INITRANS
TABLE_LOCK_ENABLE	SYSTEM
TABLE_LOCK_MODE
TABLE_MAXTRANS
TABLESPACE_LOCK_ENABLE	BOTH
TEMP_MAX_PAGE_COUNT	SYSTEM
TEMP_STATS_WATCH_TIME	SYSTEM
THREAD_CPU_AFFINITY
THREAD_REUSE_ENABLE
TIMED_STATISTICS	SYSTEM
TIMER_RUNNING_LEVEL
TIMER_THREAD_RESOLUTION	SYSTEM
TOP_RESULT_CACHE_MODE	BOTH
	SYSTEM
TOUCH_TIME_INTERVAL	SYSTEM
TRANSACTION_SEGMENT_COUNT	SYSTEM
TRX_UPDATE_MAX_LOGSIZE	BOTH
S	Normal	CM_DISCONN_DETECT_TIME
		CONCURRENT_EXEC_DEGREE_DEFAULT	SYSTEM
		CONCURRENT_EXEC_DEGREE_MAX
		CONCURRENT_EXEC_WAIT_INTERVAL	SYSTEM
		DEFAULT_THREAD_STACK_SIZE
		IPC_CHANNEL_COUNT
		IPC_FILEPATH
		IPCDA_CHANNEL_COUNT
		IPCDA_DATABLOCK_SIZE	SYSTEM
		IPCDA_FILEPATH
		MAX_LISTEN
		MAX_STATEMENTS_PER_SESSION	BOTH
		NET_CONN_IP_STACK
		NLS_COMP
		NLS_CURRENCY	SESSION
		NLS_ISO_CURRENCY	SESSION
		NLS_NCHAR_CONV_EXCP	SESSION
		NLS_NCHAR_LITERAL_REPLACE	SESSION
		NLS_NUMERIC_CHARACTERS	SESSION
		NLS_TERRITORY	SESSION
		PORT_NO
		PSM_CURSOR_OPEN_LIMIT	SYSTEM
		PSM_FILE_OPEN_LIMIT	SYSTEM
		TIME_ZONE	SESSION
		UNIXDOMAIN_FILEPATH
		USE_MEMORY_POOL
		USER_LOCK_POOL_INIT_SIZE	SYSTEM
		USER_LOCK_REQUEST_CHECK_INTERVAL	SYSTEM
		USER_LOCK_REQUEST_LIMIT	SYSTEM
		USER_LOCK_REQUEST_TIMEOUT	SYSTEM
		XA_HEURISTIC_COMPLETE
	Time-Out	BLOCK_ALL_TX_TIME_OUT	SYSTEM
		DDL_LOCK_TIMEOUT	SYSTEM
		DDL_TIMEOUT	BOTH
		FETCH_TIMEOUT	BOTH
		IDLE_TIMEOUT	BOTH
		LOGIN_TIMEOUT	SYSTEM
		MULTIPLEXING_POLL_TIMEOUT	SYSTEM
		QUERY_TIMEOUT	BOTH
		SHUTDOWN_IMMEDIATE_TIMEOUT	SYSTEM
		UTRANS_TIMEOUT	BOTH
		XA_INDOUBT_TX_TIMEOUT
T		AUTO_COMMIT	SYSTEM
		ISOLATION_LEVEL
		TRANSACTION_TABLE_SIZE
B		ARCHIVE_DIR
		ARCHIVE_FULL_ACTION
		ARCHIVE_MULTIPLEX_COUNT
		ARCHIVE_MULTIPLEX_DIR
		ARCHIVE_THREAD_AUTOSTART
		CHECKPOINT_ENABLED
		CHECKPOINT_INTERVAL_IN_LOG	SYSTEM
		CHECKPOINT_INTERVAL_IN_SEC	SYSTEM
		COMMIT_WRITE_WAIT_MODE	BOTH
		INCREMENTAL_BACKUP_CHUNK_SIZE
		INCREMENTAL_BACKUP_INFO_RETENTION_PERIOD
		LOG_BUFFER_TYPE
		LOG_MULTIPLEX_COUNT
		LOG_MULTIPLEX_DIR
		PREPARE_LOG_FILE_COUNT
		SNAPSHOT_MEM_THRESHOLD	SYSTEM
		SNAPSHOT_DISK_UNDO_THRESHOLD	SYSTEM
R		REPLICATION_ACK_XLOG_COUNT
		REPLICATION_ALLOW_DUPLICATE_HOSTS	SYSTEM
		REPLICATION_BEFORE_IMAGE_LOG_ENABLE	SYSTEM
		REPLICATION_COMMIT_WRITE_WAIT_MODE	SYSTEM
		REPLICATION_CONNECT_RECEIVE_TIMEOUT	SYSTEM
		REPLICATION_CONNECT_TIMEOUT	SYSTEM
		REPLICATION_DDL_ENABLE	SYSTEM
		REPLICATION_DDL_ENABLE_LEVEL
		REPLICATION_DDL_SYNC	SYSTEM
		REPLICATION_DDL_SYNC_TIMEOUT
		REPLICATION_EAGER_PARALLEL_FACTOR
		REPLICATION_EAGER_RECEIVER_MAX_ERROR_COUNT	SYSTEM
		REPLICATION_FAILBACK_INCREMENTAL_SYNC
		REPLICATION_GAP_UNIT
		REPLICATION_GAPLESS_ALLOW_TIME	SYSTEM
		REPLICATION_GAPLESS_MAX_WAIT_TIME	SYSTEM
		REPLICATION_GROUPING_AHEAD_READ_NEXT_LOG_FILE	SYSTEM
		REPLICATION_GROUPING_TRANSACTION_MAX_COUNT	SYSTEM
		REPLICATION_HBT_DETECT_HIGHWATER_MARK	SYSTEM
		REPLICATION_HBT_DETECT_TIME	SYSTEM
		REPLICATION_IB_LATENCY
		REPLICATION_IB_PORT_NO
		REPLICATION_INSERT_REPLACE	SYSTEM
		REPLICATION_KEEP_ALIVE_CNT
		REPLICATION_LOCK_TIMEOUT	SYSTEM
		REPLICATION_LOG_BUFFER_SIZE
		REPLICATION_MAX_COUNT
		REPLICATION_MAX_LISTEN
		REPLICATION_MAX_LOGFILE	SYSTEM
		REPLICATION_POOL_ELEMENT_COUNT	SYSTEM
		REPLICATION_POOL_ELEMENT_SIZE	SYSTEM
		REPLICATION_PORT_NO
		REPLICATION_RECEIVE_TIMEOUT	SYSTEM
		REPLICATION_RECEIVER_APPLIER_ASSIGN_MODE	SYSTEM
		REPLICATION_RECEIVER_APPLIER_QUEUE_SIZE	SYSTEM
		REPLICATION_PREFETCH_LOGFILE_COUNT	SYSTEM
		REPLICATION_RECOVERY_MAX_LOGFILE
		REPLICATION_RECOVERY_MAX_TIME
		REPLICATION_SENDER_AUTO_START
		REPLICATION_SENDER_COMPRESS_XLOG	SYSTEM
		REPLICATION_SENDER_ENCRYPT_XLOG
		REPLICATION_SENDER_SEND_TIMEOUT	SYSTEM
		REPLICATION_SENDER_SLEEP_TIME
		REPLICATION_SENDER_SLEEP_TIMEOUT	SYSTEM
		REPLICATION_SENDER_START_AFTER_GIVING_UP	SYSTEM
		REPLICATION_SERVER_FAILBACK_MAX_TIME
		REPLICATION_SQL_APPLY_ENABLE
		REPLICATION_SYNC_APPLY_METHOD	SYSTEM
		REPLICATION_SYNC_LOCK_TIMEOUT	SYSTEM
		REPLICATION_SYNC_LOG
		REPLICATION_SYNC_TUPLE_COUNT	SYSTEM
		REPLICATION_TIMESTAMP_RESOLUTION	SYSTEM
		REPLICATION_TRANSACTION_POOL_SIZE	SYSTEM
		REPLICATION_UPDATE_REPLACE	SYSTEM
NM		IB_CONCHKSPIN
		IB_ENABLE
		IB_LATENCY
		IB_LISTEN_DISABLE
		IB_MAX_LISTEN
		IB_PORT_NO	SYSTEM
		SNMP_ALARM_QUERY_TIMEOUT
		SNMP_ALARM_FETCH_TIMEOUT
		SNMP_ALARM_UTRANS_TIMEOUT
		SNMP_ALARM_SESSION_FAILURE_COUNT
		SNMP_ENABLE
		SNMP_MSGLOG_FLAG	SYSTEM
		SNMP_PORT_NO
		SNMP_TRAP_PORT_NO
		SNMP_RECV_TIMEOUT
		SNMP_SEND_TIMEOUT
		SSL_CA
		SSL_CAPATH
		SSL_CERT
		SSL_CIPHER_LIST
		SSL_CLIENT_AUTHENTICATION
		SSL_ENABLE
		SSL_KEY
		SSL_MAX_LISTEN
		SSL_PORT_NO	SYSTEM
		TCP_ENABLE
M		ALL_MSGLOG_FLUSH	SYSTEM
		COLLECT_DUMP_INFO	SYSTEM
		DK_MSGLOG_COUNT
		DK_MSGLOG_FILE
		DK_MSGLOG_FLAG	SYSTEM
		DK_MSGLOG_RESERVE_SIZE
		DK_MSGLOG_SIZE
		DUMP_MSGLOG_COUNT
		DUMP_MSGLOG_SIZE
		DUMP_MSGLOG_RESERVE_SIZE
		ERROR_MSGLOG_COUNT
		ERROR_MSGLOG_FILE
		ERROR_MSGLOG_SIZE
		ERROR_MSGLOG_RESERVE_SIZE
		LB_MSGLOG_COUNT
		LB_MSGLOG_FILE
		LB_MSGLOG_FLAG
		LB_MSGLOG_SIZE
		MM_MSGLOG_COUNT
		MM_MSGLOG_FILE
		MM_MSGLOG_RESERVE_SIZE
		MM_MSGLOG_SIZE
		MM_SESSION_LOGGING	SYSTEM
		NETWORK_ERROR_LOG	SYSTEM
		QP_MSGLOG_COUNT
		QP_MSGLOG_FILE
		QP_MSGLOG_FLAG	SYSTEM
		QP_MSGLOG_RESERVE_SIZE
		QP_MSGLOG_SIZE
		QUERY_PROF_FLAG	SYSTEM
		QUERY_PROF_LOG_DIR	SYSTEM
		RP_CONFLICT_MSGLOG_COUNT
		RP_CONFLICT_MSGLOG_DIR
		RP_CONFLICT_MSGLOG_ENABLE
		RP_CONFLICT_MSGLOG_FILE
		RP_CONFLICT_MSGLOG_FLAG	SYSTEM
		RP_CONFLICT_MSGLOG_SIZE
		RP_MSGLOG_COUNT
		RP_MSGLOG_FILE
		RP_MSGLOG_FLAG	SYSTEM
		RP_MSGLOG_RESERVE_SIZE
		RP_MSGLOG_SIZE
		SERVER_MSGLOG_COUNT
		SERVER_MSGLOG_DIR
		ERVER_MSGLOG_FILE
		SERVER_MSGLOG_FLAG	SYSTEM
		SERVER_MSGLOG_RESERVE_SIZE
		SERVER_MSGLOG_SIZE
		SM_MSGLOG_COUNT
		SM_MSGLOG_FILE
		SM_MSGLOG_FLAG	SYSTEM
		SM_MSGLOG_RESERVE_SIZE
		SM_MSGLOG_SIZE
		TRC_MSGLOG_RESERVE_SIZE
		TRCLOG_DETAIL_PREDICATE	SYSTEM
		XA_MSGLOG_COUNT
		XA_MSGLOG_FILE
		XA_MSGLOG_FLAG	SYSTEM
		XA_MSGLOG_RESERVE_SIZE
		XA_MSGLOG_SIZE
L		DBLINK_ALTILINKER_CONNECT_TIMEOUT
		DBLINK_DATA_BUFFER_ALLOC_RATIO
		DBLINK_DATA_BUFFER_BLOCK_COUNT
		DBLINK_DATA_BUFFER_BLOCK_SIZE
		DBLINK_ENABLE
		DBLINK_GLOBAL_TRANSACTION_LEVEL
		DBLINK_RECOVERY_MAX_LOGFILE	SYSTEM
		DBLINK_REMOTE_STATEMENT_AUTOCOMMIT	BOTH
		DBLINK_REMOTE_TABLE_BUFFER_SIZE
U		AUDIT_FILE_SIZE	SYSTEM
		AUDIT_LOG_DIR	SYSTEM
		AUDIT_OUTPUT_METHOD	SYSTEM
		AUDIT_TAG_NAME_IN_SYSLOG	SYSTEM
A		EXTPROC_AGENT_CONNECT_TIMEOUT	SYSTEM
		EXTPROC_AGENT_CALL_RETRY_COUNT	SYSTEM
		EXTPROC_AGENT_IDLE_TIMEOUT	SYSTEM
		EXTPROC_AGENT_SOCKET_FILEPATH
AS		CASE_SENSITIVE_PASSWORD	SYSTEM
		FAILED_LOGIN_ATTEMPTS
		PASSWORD_LOCK_TIME
		PASSWORD_LIFE_TIME
		PASSWORD_GRACE_TIME
		PASSWORD_REUSE_TIME
		PASSWORD_REUSE_MAX
		PASSWORD_VERIFY_FUNCTION
E		ACCESS_LIST
		ACCESS_LIST_FILE
		ADMIN_MODE	SYSTEM
		ARITHMETIC_OPERATION_MODE	SESSION
		CHECK_MUTEX_DURATION_TIME_ENABLE	SYSTEM
		COERCE_HOST_VAR_IN_SELECT_LIST_TO_VARCHAR
		DEFAULT_DATE_FORMAT
		EXEC_DDL_DISABLE	SYSTEM
		GROUP_CONCAT_PRECISION	SYSTEM
		JOB_SCHEDULER_ENABLE	SYSTEM
		JOB_THREAD_COUNT
		JOB_THREAD_QUEUE_SIZE
		MSG_QUEUE_PERMISSION
		PSM_CHAR_DEFAULT_PRECISION
		PSM_IGNORE_NO_DATA_FOUND_ERROR	SYSTEM
		PSM_NCHAR_UTF16_DEFAULT_PRECISION
		PSM_NCHAR_UTF8_DEFAULT_PRECISION
		PSM_NVARCHAR_UTF16_DEFAULT_PRECISION
		PSM_NVARCHAR_UTF8_DEFAULT_PRECISION
		PSM_PARAM_AND_RETURN_WITHOUT_PRECISION_ENABLE
		PSM_VARCHAR_DEFAULT_PRECISION
		QUERY_STACK_SIZE	BOTH
		RECURSION_LEVEL_MAXIMUM	SESSION
		REMOTE_SYSDBA_ENABLE	SYSTEM
		SELECT_HEADER_DISPLAY	BOTH
		SYS_CONNECT_BY_PATH_PRECISION	SYSTEM
		SERIAL_EXECUTE_MODE	BOTH

In this chapter, each property is explained as follows:

Property name
Data type
Default value
Attributes (e.g. read-only vs. read-write, single vs. multiple values)
Range (maximum and minimum possible values)
Description

Description#

Description#

This property specifies the cache type of a table lock node. It cannot be modified during the server operation.

[64 * 1024, 2³²-1]

Description#

This property specifies the size, in bytes, of a log file. When an active log file fills up, writing continues in a new log file. This property can be set only when creating a database; it can't be changed afterwards. The user should create a new database in order to modify the log file size.

* Restriction

In order to perform offline replication, this property must be set the same on the local (active) server and the remote (standby) server.

MAX_CLIENT#

Data Type#

Unsigned Integer

Default Value#

1000

Attributes#

Read-Only, Single Value

Range#

[0, 65535]

However, if the value of JOB_THREAD_COUNT property is set to greater than 0, the maximum value is obtained by subtracting the value of the JOB_THREAD_COUNT property from 65535.

Description#

This is used to specify the maximum number of clients which can be accessed to the Altibase.

MEM_DB_DIR#

Data Type#

String

Default Value#

\$ALTIBASE_HOME/dbs

Attributes#

Read-Only, Multiple Values

Range#

None

Description#

This property specifies the pathname for the memory database files.

It is possible to specify a minimum of 1 to a maximum of 8 paths. If multiple paths are specified, the database files are distributed among the paths. All of the paths specified using this property must be actual existing paths. The default number of paths is two, and they are both set to $ALTIBASE_HOME/dbs.

MEM_MAX_DB_SIZE (Unit: byte)#

Data Type#

Unsigned Long

Default Value#

2³¹

Attributes#

Read-Only, Single Value

Range#

Range#

[50, 99]

Description#

In a memory B+ tree index, when the last child node of a leaf node in the lowest rank is divided, the MEMORY_INDEX_UNBALANCED_SPLIT_RATE property sets the ratio by which to divide keys between the node to be divided and the created node.

When this value is set to 50, which is the default value, the key ratio between the 2 nodes is 50:50.

The user can change the value of the MEMORY_INDEX_UNBALANCED_SPLIT_RATE property using the ALTER SYSTEM statement while Altibase is running.

MEMORY_LOB_COLUMN_IN_ROW_SIZE (Unit: bytes)#

Data Type#

Unsigned Long

Default Value#

64

Attributes#

Read-Only, Single Value

Range#

[0,4000]

Description#

This property sets the default column size, in bytes, when LOB type data are stored directly in memory tables.

When data are entered into a LOB data type column, if the data length is smaller or the same as the value specified here, they are saved in a fixed amount of area, whereas if the data are larger than this value, they are saved in a variable area. This property pertains only to memory tables, and has no effect on how disk tables are managed.

For more detailed information about LOB type data, please refer to Chapter1: Data Types.

MEMORY_VARIABLE_COLUMN_IN_ROW_SIZE (Unit: bytes)#

Data Type#

Unsigned Long

Default Value#

32

Attributes#

Read-Write, Single Value

Range#

[0,4000]

Description#

Description#

This property specifies the number of additional bytes allocated by the system each time the Query Processor requires additional memory.

RECYCLEBIN_DISK_MAX_SIZE (Unit: byte)#

Data Type#

Unsigned Long

Default Value#

2⁶⁴-1

Attributes#

Read-Only, Single Value

Range#

[0, 2⁶⁴-1]

Description#

Specifies the size of the recycle bin (in bytes) to which disk tables are moved.

The value of this property can be changed using the ALTER SYSTEM statement while Altibase is running.

RECYCLEBIN_ENABLE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

When a table is dropped with the DROP statement, RECYCLEBIN_ENABLE specifies whether a table is to be moved to a recycle bin or dropped directly from the database system.

If the recycle bin contains a table, the table can be queried or recovered/dropped with the FLASHBACK or PURGE statement, even if the value of this property is altered to 0.

The value of this property can be changed using the ALTER SYSTEM statement while Altibase is running.

0 : Disable(default) - The table is dropped from the database.

1 : Enable - The table is moved to the recycle bin.

RECYCLEBIN_MEM_MAX_SIZE (Unit: byte)#

Data Type#

Unsigned Long

Default Value#

4 GB

Attributes#

Read-Write, Single Value

Range#

[0, 2⁶⁴-1]

Description#

Specifies the size of the recycle bin to which memory tables are dropped. The value of this property can be changed using the ALTER SYSTEM statement while Altibase is running.

REDUCE_TEMP_MEMORY_ENABLE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

This property can minimize the space occupied by data of variable-length columns, when the data is temporarily stored in the memory tablespace.

The disk temporary tablespace is where the Altibase server temporarily stores intermediate results by default, when processing queries on disk tables or views. To enhance performance, intermediate results can be stored in the memory tablespace, using the TEMP_TBS_MEMORY hint(please refer to Administrator's Manual and Performance Tuning Guide).

The default value 0 can occupy unnecessary space, due to data of variable-length columns using temporary storage space of a fixed length, as data of fixed-length columns do. To reduce such waste of space, this property can be set to 1 and only as much space as the actual data of the variable-length column is used. While memory usage is smaller, however, the speed of query processing can slow down.

[30, 2³²-1]

Description#

This property specifies the number of times necessary for the thread manager to check the status of standby service threads, in order to destroy the threads. If the standby service threads are not allocated a client for the number of times the thread manager has set for this property, they are destroyed.

Service threads are placed on standby when they are allocated a smaller number of clients than the value set for the MIN_TASK_COUNT_FOR_THREAD_LIVE property.

The value of this property can be changed using the ALTER SYSTEM statement while Altibase is running.

SMALL_TABLE_THRESHOLD#

Data Type#

Unsigned Integer

[²] The initial extent size cannot be changed after the database has been created. The default value is 32 pages.

SYS_TEMP_FILE_INIT_SIZE (Unit: byte)#

Data Type#

Unsigned long

Default Value#

100M (100 * 1024 * 1024)

Attributes#

Read-Only, Single Value

Range#

[ 8 * 8kB, 32GB]

Description#

This specifies the initial size, in bytes, of the temporary data file (temp001.dbf) when SYS_TBS_DISK_TEMP is created. Moreover, if the initial size is not specified when a temporary data file is added to SYS_TBS_DISK_TEMP, the value specified here is used.

SYS_TEMP_FILE_MAX_SIZE (Unit: byte)#

Data Type#

Unsigned long

Default Value#

2 * 1024 * 1024 * 1024

Attributes#

Read-Only, Single Value

Range#

[8 * 8K, 32GB]

Description#

This specifies the maximum size, in bytes, of the data file (temp001.dbf) that is allocated when SYS_TBS_DISK_TEMP is created.

The value of this property must be at least as great as that of SYS_TEMP_FILE_INIT_SIZE. The minimum possible value is 64kB. Moreover, if the maximum size is not specified when a temporary data file is added to SYS_TBS_DISK_TEMP, the size specified here is the default maximum size.

SYS_TEMP_FILE_NEXT_SIZE (Unit: byte)#

Data Type#

Unsigned long

Default Value#

1 * 1024 * 1024

Attributes#

Read-Only, Single Value

Range#

[8 * 8kB, 32GB]

Description#

If there is not enough space in a data file in the SYS_TBS_DISK_TEMP tablespace, the size of the file is increased by the amount specified here.

SYS_TEMP_TBS_EXTENT_SIZE (Unit: byte)#

Data Type#

Unsigned long

Default Value#

256 * 1024

Attributes#

Read-Only, Single Value

Range#

[40kB, 32GB]

Description#

This specifies the size, in bytes, of an extent when the SYS_TBS_DISK_TEMP (system disk temporary tablespace)³ is created.

It must be large enough to contain at least five pages (40kB = 5 * 8kB).

[³] System disk temporary tablespace:

This is automatically created by default when a database is created, and is a tablespace for temporary storage related to various kinds of database operations. It is set as the default temporary tablespace for storing objects on disk for all users. The only database objects that are stored here are disk tables and disk indexes.

SYS_UNDO_FILE_INIT_SIZE (Unit: byte)#

Data Type#

Unsigned long

Default Value#

100 * 1024 * 1024

Attributes#

Read-Only, Single Value

Range#

[32 * 8kB, 32GB]

Description#

This specifies the default size, in bytes, of the data file (undo001.dbf) when the SYS_TBS_DISK_UNDO tablespace is created. Additionally, when a data file is added to SYS_TBS_DISK_UNDO without specifying its initial size, the size specified here is used.

SYS_UNDO_FILE_MAX_SIZE (Unit: byte)#

Data Type#

Unsigned long

Default Value#

2 * 1024 * 1024 * 1024

Attributes#

Read-Only, Single Value

Range#

[32 * 8kB, 32GB]

Description#

This specifies the maximum size, in bytes, of the data file (undo001.dbf) that is allocated when the SYS_TBS_DISK_UNDO is created.

The value of this property must be at least as great as that of SYS_UNDO_FILE_INIT_SIZE. The minimum possible value is 256kB. Moreover, if the maximum size is not specified when a temporary data file is added to SYS_TBS_DISK_UNDO, the value specified here is used as the default maximum size.

SYS_UNDO_FILE_NEXT_SIZE (Unit: byte)#

Data Type#

Unsigned long

Default Value#

1 * 1024 * 1024

Attributes#

Read-Only, Single Value

Range#

[8 * 8kB, 32GB]

Description#

When there is not enough space in the SYS_TBS_DISK_UNDO tablespace data file, the size of the data file is incremented by the number of bytes specified here.

SYS_UNDO_TBS_EXTENT_SIZE (Unit: byte)#

Data Type#

Unsigned long

Data Type#

Unsigned Integer

Default Value#

1

Attributes#

Read-Only, Single Value

Range#

[1, 50]

Description#

Description#

This sets the maximum size, in bytes, of a user-defined data file that is created or added to a user disk data tablespace.

The value of this property should be at least as big as that specified in USER_DATA_FILE_INIT_SIZE. The minimum possible value is 64kB. If no maximum size is specified when a data file is created or added, the default value specified here is used.

USER_DATA_FILE_NEXT_SIZE (Unit: byte)#

Data Type#

Unsigned long

Default Value#

1 * 1024 * 1024

Attributes#

Read-Only, Single Value

Range#

[8 * 8kB, 32GB]

Description#

If the data file in the user-defined data file of the user disk data tablespace lacks space, the data file size is increased as specified for this property.

USER_DATA_TBS_EXTENT_SIZE (Unit: byte)#

Data Type#

Unsigned long

Default Value#

512 * 1024

Attributes#

Read-Only, Single Value

Range#

[2 * 8kB, 2⁶⁴-1]

Description#

This specifies the size, in bytes, of an extent when a user disk data tablespace⁵ is created.

[⁵] User disk data tablespace:

This is a tablespace for storing user objects. Only disk tables and disk indexes are stored among database objects.

USER_TEMP_FILE_INIT_SIZE (Unit: byte)#

Data Type#

Unsigned long

Default Value#

100 * 1024 * 1024

Attributes#

Read-Only, Single Value

Range#

[8 * 8kB, 32GB]

Description#

This specifies the initial size, in bytes, of a data file when a user-defined temporary data file is created or added to a user temporary tablespace. If no initial size is specified, the default value specified here is used.

USER_TEMP_FILE_MAX_SIZE (Unit: byte)#

Data Type#

Unsigned long

Default Value#

2 * 1024 * 1024 * 1024

Attributes#

Read-Only, Single Value

Range#

[8 * 8kB, 32GB]

Description#

This property limits the maximum size, in bytes, of user-defined temporary data files that are created in or added to a user temporary tablespace.

This parameter must be at least as great as USER_DATA_FILE_INIT_SIZE. The minimum possible value is 64kB. If no maximum size is specified when temporary data files are created or added, the default value specified here is used.

USER_TEMP_FILE_NEXT_SIZE (Unit: byte)#

Data Type#

Unsigned long

Default Value#

1 * 1024 * 1024

Attributes#

Read-Only, Single value

Range#

[8 * 8kB, 32GB]

Description#

If there is insufficient space in a user-defined temporary data file in a user temporary tablespace, the size of the data file is increased by the number of bytes specified here.

USER_TEMP_TBS_EXTENT_SIZE (Unit: byte)#

Data Type#

Attributes#

Read-Write, Single Value

Range#

[0, 100]

This property specifies the number of buffer pages (frames) that can be flushed in one flusher cycle when checkpoint flushing.

CHECKPOINT_FLUSH_MAX_GAP (Unit: log files count)#

Data Type#

Unsigned Integer

Default Value#

10

Attributes#

Read-Write, Single Value

Range#

[0, 2³²-1]

Description#

Description#

This property enables the Altibase dispatcher to select the system call for detecting sockets. If there are more than 1,000 concurrent client connections, using the POLL() system call helps improve performance.

1: SELECT() system call
2: POLL() system call; available for use only on supported operating systems
3: EPOLL() system call; available for use only on supported operating systems

DATABASE_IO_TYPE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Only, Single Value

Range#

[0, 1]

Description#

Altibase provides two disk I/O methods related to database files:

Direct I/O
Buffered I/O

To use direct I/O, set this parameter to 1, or to use buffered I/O, set it to 0.

The advantage of Direct I/O is that it reduces CPU resources during the occurrence of Disk I/O. On the other hand, since buffered I/O uses the read-ahead and asynchronous write techniques, it does not necessarily incur disk access every time disk I/O is requested. This means that buffered I/O can realize better performance than direct I/O from the aspect of client applications; however, buffered I/O consumes more CPU resources than direct I/O.

DATAFILE_WRITE_UNIT_SIZE (Unit: count)#

Data Type#

Unsigned Long

Default Value#

1024

Attributes#

Read-Write, Single Value

Range#

[1, 1024]

This property specifies the number of initial service threads to be created in dedicated thread mode. This property is only valid if the value of the DEDICATED_THREAD_MODE property is 1.

The value of the DEDICATED_THREAD_INIT_COUNT property must be smaller than the value set in the DEDICATED_THREAD_MAX_COUNT property.

DEDICATED_THREAD_MAX_COUNT#

Data Type#

Unsigned Integer

Default Value#

1

Attributes#

Read-Only, Single Value

Range#

[0, 65535]

Description#

This property specifies the maximum number of service threads to be created in dedicated thread mode. This property is only valid if the value of the DEDICATED_THREAD_MODE property is 1.

If all of the initial service threads created are allocated to clients, the number of service threads can increase up to the value of the DEDICATED_THREAD_MAX_COUNT property.

The value of the DEDICATED_THREAD_MAX_COUNT property must be smaller than the value set in the MAX_CLIENT property.

DEDICATED_THREAD_MODE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Only, Single Value

Range#

[0, 1]

Description#

This property specifies whether or not service threads are to be run in dedicated thread mode for clients.

1: Service threads run in dedicated mode
0: Service threads run in multiplexing mode

Description#

This property specifies whether or not the log buffer can be simultaneously accessed by multiple threads of the server. If the value of this property is set to 0, multiple server threads can sequentially access the log buffer; if the value of this property is set to 1, server threads can simultaneously access the log buffer.

0: Simultaneous access is disabled.

1: Simultaneous access is enabled.

HASH_AREA_SIZE (Unit: byte)#

Data Type#

Unsigned Long

Default Value#

4MB

Attributes#

Read-Write, Single Value

Range#

[3M, 2⁶⁴-1]

Description#

This property specifies the memory size, in bytes, of each temporary table that the server uses for hashing operations.

The value of this property can be changed using the ALTER SYSTEM statement while Altibase is running.

HASH_JOIN_MEM_TEMP_AUTO_BUCKET_COUNT_DISABLE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

Sets the necessary number of buckets for memory hash temporary tables used in hash joins.

0 : The number of actual records inserted into a hash table.
1 : The number of buckets predicted by the query optimizer or set with the /+ HASH BUCKET COUNT () / hint.

If the value for the HASH_JOIN_MEM_TEMP_PARTITIONING_DISABLE property is 0 (partitioning method), it is efficient to divide as many sections as there are buckets.

If the value for the HASH_JOIN_MEM_TEMP_PARTITIONING_DISABLE property is 1 (bucket method), the number of buckets is predicted by the query optimizer or set by a hint.

The value of the HASH_JOIN_MEM_TEMP_PARTITIONING_DISABLE property can be altered using the ALTER SYSTEM statement while Altibase is running.

HASH_JOIN_MEM_TEMP_PARTITIONING_DISABLE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

Sets how to insert records into and scan memory hash temporary tables that are used in hash joins.

0 : Partitioning method

[1, 512]

Description#

Description#

Description#

This property specifies the maximum size, in bytes, for LOB data capable of being stored on the client LOB cache. If a value larger than 0 is specified for this property, LOB data that does not exceed the specified value is temporarily stored on the client; if 0 is specified for this property, LOB data is not temporarily stored on the client.

If the threshold is appropriately adjusted with the use of this property, LOB data is stored on the client LOB cache and Bulk-select speed is improved.

This property can be changed using either the ALTER SYSTEM or ALTER SESSION statement while Altibase is running.

LOCK_ESCALATION_MEMORY_SIZE (Unit: byte)#

Data Type#

Unsigned Integer

Default Value#

100M

Attributes#

Read-Write, Single Value

Range#

[0, 1000MB]

Description#

This property is used to prevent abnormal increases in memory usage due to versioning when large-volume UPDATE batch tasks are performed on memory tables. If the size of logs created by a DML statement increases beyond the value specified in this property, so-called “in-place update”⁶ is performed without versioning in order to prevent increased memory usage.

[⁶] In-place update” means directly updating the value of a column in an original record without creating another version of the record.

When using versioning while updating records, an X lock is placed on the record, and an IX lock is placed on the table. However, when in-place update is performed, an X lock, that is, an exclusive lock, is placed on the table. Therefore, care must be taken when setting this value as it can degrade the scalability of the corresponding table if the value is set too low. This property value can be changed using the ALTER SYSTEM statement while A is running.

This property can be changed using the ALTER SYSTEM statement while Altibase is running.

LOG_IO_TYPE#

Data Type#

Unsigned Integer

Default Value#

1

Attributes#

Read-Only, Single Value

Range#

[0, 1]

Description#

This indicates the I/O mode used to write logs.

0: buffered I/O

1: direct I/O

LOG_CREATE_METHOD#

Data Type#

Unsigned Integer

Default Value#

0 (on HP-UX or AIX Environment)
1 (on Linux Environment)

Default Value#

1

Attributes#

Read-Only, Single Value

Range#

[0, 1]

Description#

The MEM_INDEX_KEY_REDISTRIBUTION property redistributes memory index keys.

This property is highly efficient to use for inserting numerous reverse index keys, a lot of leaf node splits, or when the index range is much larger than that of the database.

0: The memory index keys are not redistributed.

1: The memory index keys are redistributed (Default value).

The value of this property can be changed using the ALTER SYSTEM statement while Altibase is running.

MEM_INDEX_KEY_REDISTRIBUTION_STANDARD_RATE#

Data Type#

Unsigned Integer

Default Value#

50

Attributes#

Read-Only, Single Value

Range#

[10, 90]

Description#

The MEM_INDEX_KEY_REDISTRIBUTION_STANDARD_RATE property sets up the minimum values for ratio of unused space in order to redistribute the memory index keys. For example, if the value of this property is 30, the memory key indexes are redistributed when there is at least minimum 30% of unused space of leaf nodes

MEM_INDEX_KEY_REDISTRIBUTION property would not be working if it is set to 0.

The value of this property can be changed using the ALTER SYSTEM statement while Altibase is running.

MULTIPLEXING_CHECK_INTERVAL(Unit: microsecond)#

Data Type#

Unsigned Integer

Default Value#

200000

Attributes#

Read-Write, Single Value

Range#

[100000, 10000000]

Description#

This property indicates the interval at which sessions are checked, so that the thread manager service thread can be distributed. It is expressed in units of microseconds.

The thread manger periodically checks the status of threads, updates statistical data, and adds and deletes service threads.

MULTIPLEXING_MAX_THREAD_COUNT#

Data Type#

Unsigned Integer

Default Value#

1024

Attributes#

Read-Write, Single Value

Range#

[1, 1024]

Description#

This is the maximum number of multiplex threads.

If the capacity of existing threads is exceeded, new threads are automatically added. However, because performance can suffer if new threads are continually created, care must be taken to set this property appropriately.

Nevertheless, when queuing (QUEUE) is used, a number of threads exceeding the value specified by this property can be created.

MULTIPLEXING_THREAD_COUNT#

Data Type#

Unsigned Integer

Default Value#

The number of logical cores

Attributes#

Read-Only, Single Value

Range#

[1, 1024]

Description#

This is the minimum number of shared service threads that Altibase keeps running. The default is the number of logical cores.

This parameter cannot be changed after the server has been started.

NORMALFORM_MAXIMUM#

Data Type#

Unsigned Integer

Default Value#

2048

Range#

Read-Write, Single Value

Range#

[1, 2³²-1]

Description#

This property specifies the maximum number of normal form nodes when normalizing a condition clause.

When the predicates in a WHERE statement of a SELECT query are complicated by the use of logical operators (AND, OR), Altibase normalizes the predicates so that the table(s) can be searched more quickly.

There are two normalization methods: Conjunctive Normal Form (CNF) and Disjunctive Normal Form (DNF). If the use of either of these normal forms results in the number of nodes specified here being exceeded, no attempt to perform normalization using that normal form is made.

If both of the normal forms exceed the number specified here, execution proceeds Not Normal Form(NNF) without the condition clause being normalized. Using the NNF method, the condition is not normalized and the index can not be used.

On the other hand, if the value specified here is set to a larger number to avoid the NNF, the process of normalizing the complicated condition clause can use vast amounts of memory, thus the normalizing process itself becomes so expensive

Therefore, it is important to avoid the excessive use of logical operators when writing condition clauses, and to write condition clauses in normal forms.

Similarly, this rule also applies to an ON predicate joined to an ON condition.

OPTIMIZER_AUTO_STATS#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 10]

Description#

This property can automatically collects statistical information when there is no available statistical information the optimizer can use.

The number of collectable pages range from 1 to 10 as described below. If it is set to 0, the statistical information cannot be automatically collected.

This property can be changed by using the ALTER SESSION and SYSTEM statements while the system is running.

Value	Pages	Collection Status for gathering statistics (ON/OFF)
0(Default value)	0	OFF
1	32	ON
2	64	ON
3	128	ON
4	256	ON
5	512	ON
6	1024	ON
7	4096 (32M)	ON
8	16384 (128M)	ON
9	65536 (512M)	ON
10	ALL	ON

OPTIMIZER_DELAYED_EXECUTION#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

This property performs execution of hierarchy, sorting, windowing, grouping, set, and distinction in fetch based upon execution plan graphs. The user can check the added DELAY plan under the top PROJECTION in the execution plan

This property reduces execution time and extends the first fetch time by delaying execution to be carried out in the first fetch when executing a query. The first fetch time remains the same, and the execution time can be viewed with the performance view V$STATEMENT.

0 : disable (Deactivated, Default value)

1 : enable (Activated)

This property can be modified with the ALTER SESSION during the Altibase operation.

OPTIMIZER_FEATURE_ENABLE#

Data Type#

String

Default Value#

Altibase Server Version

Attributes#

Read-Write, Single Value

Range#

[6.1.1.0.6 | 6.1.1.0.7 | 6.3.1.0.1 | 6.5.1.0.0| 7.1.0.0.0]

Description#

This property controls properties related to the query optimizer in a uniform manner.

Only the versions specified in the range of this property can be altered with the ALTER SYSTEM statement.

e.g) ALTER SYSTEM SET optimizer_feature_enable = '6.1.1.0.6';

The following table shows how values of properties related to the query optimizer are set according to the settings of this property

OPTIMIZER_FEATURE_ENABLE	6.3.1.0.1	6.5.1.0.0	7.1.0.0.0
QUERY_REWRITE_ENABLE	0 (off)	0 (off)	0 (off)
OPTIMIZER_UNNEST_SUBQUERY	1 (on)	1 (on)	1 (on)
OPTIMIZER_UNNEST_COMPLEX_SUBQUERY	1 (on)	1 (on)	1 (on)
OPTIMIZER_UNNEST_AGGREGATION_SUBQUERY	0 (off)	1 (on)	1 (on)
RESULT_CACHE_ENABLE	0 (off)	0 (off)	0 (off)
TOP_RESULT_CACHE_MODE	0 (off)	0 (off)	0 (off)
OPTIMIZER_AUTO_STATS	0 (off)	0 (off)	0 (off)
OPTIMIZER_PERFORMANCE_VIEW	0 (off)	0 (off)	1 (on)

OPTIMIZER_MODE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

If this property is set to 0, cost-based optimization will be used to optimize query statements, whereas if it is set to 1, rule-based optimization will be used.

This property can be changed using the ALTER SYSTEM or ALTER SESSION statement while Altibase is running.

OPTIMIZER_PERFORMANCE_VIEW#

Data Type#

Unsigned Integer

Default Value#

1

Attributes#

Read-Only, Single Value

Range#

[0, 1]

Description#

This property configures whether or not to set a constraint on the memory. Internal enhancement can be expected when monitoring information of Altibase system

0: (Not apply) : There is no constraints on the memory.

1: {Apply, Default Value) : Memory constraints exist. If the value of EXECUTE_STMT_MEMORY_MAXIMUM exceeds, query execution fails.

OPTIMIZER_UNNEST_AGGREGATION_SUBQUERY#

Data Type#

Unsigned Integer

Data Type#

Unsigned Integer

Default Value#

1

Attributes#

Read-Only, Single Value

Range#

[0, 1]

Description#

This property allows the user to execute an optimized query plan by specifying that an outer join operation supported by the ANSI/ISO SQL standard is to be performed.

[0, 1]

Description#

This property specifies whether or not to apply function-based indexes on query conversion by the Altibase server.

0: disable

1: enable

REFINE_PAGE_COUNT#

Data Type#

Unsigned Integer

Default Value#

50

Attributes#

Read-Only, Single Value

Range#

[0, 2³²-1]

Description#

One of the Altibase startup steps handles database refinement. When the Altibase server was shut down the previous time, some so-called “versioning records” created by transactions are not handled by the garbage collector, and thus unneeded records may exist in the database, and furthermore, other versioning records created by recovery processes when the server is started up may also exist. The database refining step is conducted so that these records can be reused.

Because this process can be time-consuming when many records are to be refined, it is conducted in parallel by multiple threads. This property specifies the number of pages handled by each thread.

RESULT_CACHE_ENABLE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

This is a property that uses the result cache to save the execution plan of intermediate results.

0: Disabled (Default value) – Do not use the cache function

1: Enabled – Use the cache function

This property may be changed using the ALTER SYSTEM or ALTER SESSION statement while Altibase is running.

RESULT_CACHE_MEMORY_MAXIMUM (Unit: byte)#

Data Type#

Unsigned Long

Default Value#

10M

Attributes#

Read-Write, Single Value

Range#

[4096, ULONG MAX]

Description#

When using result cache and top result cache, it limits the amount of memory to store. If this size is exceeded, it is not stored in memory but released. This property is a constraint for one query and does not provide a system-wide constraint.

This property may be changed using the ALTER SYSTEM statement while Altibase is running.

SECONDARY_BUFFER_ENABLE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Only, Single Value

Range#

[0, 1]

Description#

The secondary buffer feature is the flushing of data pages of a memory buffer to the secondary buffer of an SSD(Solid-state Drive) first, instead of flushing them immediately to disk. The data pages of a secondary buffer are flushed to disk by a separate thread within the Altibase server

[0, 2]

Description#

This property specifies the data page type which is to be stored in the secondary buffer. One of the following values can be specified:

0: Pages of all types

1: Dirty pages

2: Clean pages

For more detailed information about the secondary buffer feature, please refer to the description of the SECONDARY_BUFFER_ENABLE property.

SORT_AREA_SIZE (Unit: byte)#

Data Type#

Unsigned long

Default Value#

1048576

Attributes#

Read-Write, Single Value

Range#

[512, 2⁶⁴-1]

Description#

This property specifies the memory size, in bytes, of each temporary table that the server uses for sorting operations.

This property can be changed using the ALTER SYSTEM statement while the system is running.

SQL_PLAN_CACHE_BUCKET_CNT#

Data Type#

Unsigned Integer

Default Value#

127

Attributes#

Read-Only, Single Value

Range#

[5, 4096]

Description#

This property indicates the number of hash table buckets in a SQL plan cache.

SQL_PLAN_CACHE_HOT_REGION_LRU_RATIO (Unit: percentage)#

Data Type#

Unsigned Integer

Default Value#

50

Attributes#

Read-Write, Single Value

Range#

[10, 100]

Description#

This property indicates the percentage of a hot area in an LRU list in a SQL plan cache. A HOT area in an LRU list is a separate portion of an LRU list in a SQL plan cache in which plans that are referred to frequently are saved.

This property can be changed using the ALTER SYSTEM statement while the system is running.

SQL_PLAN_CACHE_PREPARED_EXECUTION_CONTEXT_CNT#

Data Type#

Unsigned Integer

Default Value#

1

Attributes#

Read-Write, Single Value

Range#

[0, 1024]

Description#

Description#

This property indicates the initial number of TTS (Touched Transaction Slots) to be maintained in a table page.

TABLE_LOCK_ENABLE#

Data Type#

Unsigned Integer

Default Value#

1

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

This property controls the lock level.

0: This does not support the table lock, but the record lock. Efficiency is improved when using it on a simple DML.

1: This supports the table and record lock.

If the value of this property is set to 0, the following restrictions are applied:

DDL statements cannot be executed.
CREATE DATABASE cannot be executed.
Parallel SYNC cannot be used when performing replication.

This property can be changed using the ALTER SYSTEM statement.

TABLE_LOCK_MODE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Only, Single Value

Range#

[0, 1]

Description#

This property controls the lock level of a table partition lock. This property is available for use only if the TABLE_LOCK_ENABLE is set to 1.

0: Table partition lock is supported. If the partition lock is used, the simultaneity is enhanced when using a query statement executing per a partition, such as ALTER TABLE…TRUNCATE PARTITION.

1: This does not support the table partition lock, it is identical with the lock on a non-partitioned table of a partitioned table. DML performance is much more improved due to the reduced lock count.

TABLE_MAXTRANS#

Data Type#

Unsigned Integer

Default Value#

120

Attributes#

Read-Only, Single Value

Range#

[0, 120]

Description#

This property indicates the maximum size of the TTS (Touched Transaction Slots) that is maintained for one table page.

TABLESPACE_LOCK_ENABLE#

Data Type#

Unsigned Integer

Default Value#

1

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

This property specifies the lock level for tablespaces.

1: Locks for table spaces are supported.com

0: Locks for tablespaces are unsupported. In this case, the processing speed is enhanced for the execution of simple DML statements; however, the following restrictions apply.

DDL statements cannot be executed.
The CREATE DATABASE statement cannot be executed.
Parallel Synchronization for replication is not supported.

The value of this property can be changed using the ALTER SYSTEM or the ALTER SESSION statement while Altibase is running. However, it can only be changed in the absence of activated transactions

TEMP_STATS_WATCH_TIME#

Data Type#

Unsigned Int

Default Value#

10

Attributes#

Read-Write, Single Value

Range#

[0, 2³²-1]

Description#

This property specifies the standard time to be registered for statistical information. Among the operations using temporary tables, operations that take longer than the value specified for this property are registered for statistical information.

The value of this property can be changed using the ALTER SYSTEM statement while Altibase is running.

THREAD_CPU_AFFINITY#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Only, Single Value

Range#

[0, 1]

Description#

This property specifies whether or not to bind CPUs to service threads. If this is turned on, a service thread will only be assigned to the same CPU core during its execution. It will reduce costs for moving thread information from one CPU core to another CPU core.

0: Do not use CPU affinity feature
1: Use CPU affinity feature

However, logging bottlenecks can occur when using CPU affinity on HP-UX IA64. Thus, the Altibase server does not enable CPU affinity, even if the value of this property is set to 1 ( in the altibase.properties file ) on HP-UX IA64.

THREAD_REUSE_ENABLE#

Data Type#

Unsigned Integer

Default Value#

1

Attributes#

Read-Only, Single Value

Range#

[0, 1]

Description#

This property indicates whether or not to reuse threads used on internal Altibase server.

0: New threads

1: Reusing threads (default value)

When you reuse a thread, reduce the cost of creating threads because using the threads waiting in memory.

TIMED_STATISTICS#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

This property determines whether to measure the wait time for wait events and the time required for SQL operations. Using this property to specify that the time is to be measured can negatively impact performance.

0: Do not measure the time

1: Measure the time

TIMER_RUNNING_LEVEL#

Data Type#

Unsigned Integer

Default Value#

The default value for this property differs depending on the platform as follows:

1 : all platforms not listed below
2 : IBM-AIX
3 : x86-linux, Amd64-linux

Attributes#

Read-Only, Single Value

Range#

[1, 3]

Description#

This property specifies how to measure the wait time for wait events and the time required for SQL operation.

1: The time measurement thread measures the time at regular intervals specified in the property TIMER_THREAD_RESOLUTION.

2: The time is measured using the library functions provided with respective platforms.

3: This method is similar to #1, but the time is measured using the system clock. Therefore, this method doesn't hinder performance as much as the other methods.

If this property is set to 3 on OS platforms other than Linux and PA-RISC-HP-64, it may become impossible to start the Altibase server due to the inability to correctly check the system time. In this case, the Altibase server will leave a warning message in the altibase_boot.log file, reset the TIMER_RUNNING_LEVEL property to its default value, and restart. On platforms for which the default value is 1, the following message is written to the boot log:

[Warning] Because a TIMER_RUNNING_LEVEL of 3 is not supported on this platform, it has been set to the default(=1) for this platform.

TIMER_THREAD_RESOLUTION (Unit: microsecond)#

Data Type#

Unsigned Integer

Default Value#

1000

Attributes#

Read-Write, Single Value

Range#

[50, 10000000]

Description#

If TIMER_RUNNING_LEVEL is set to 1, this property specifies the time interval.

TOP_RESULT_CACHE_MODE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Only, Single Value

Range#

[0, 3]

Description#

This property sets whether to save the execution plan of the final result using the top result cache.

0: Disabled (default value) – Do not use the top result cache function

1: MEMORY - cache the final result of queries using only memory tables

2: DISK – cache the final result of queries using only disk tables

3: ALL – cache the final result of queries regardless of the table type

The value of this property can be changed using the ALTER SYSTEM or ALTER SESSION statement while Altibase is running.

TOTAL_WA_SIZE (Unit: byte)#

Data Type#

Unsigned Long

Default Value#

128MB

Attributes#

Read-Write, Single Value

Range#

[512K, 2⁶⁴-1]

Description#

This property specifies the maximum size of memory available for allocation for sorting or hashing operations.

The value of this property can be changed using the ALTER SYSTEM statement while Altibase is running. The response to a request for alteration is immediately returned, however, the altered value is not actually applied to the server until the temporary table in use is nonexistent.

INIT_TOTAL_WA_SIZE (Unit: bytes)#

Data Type#

Unsigned Long

Default Value#

128MB

Attributes#

Read-Write, Single Value

Range#

[512K, 2⁶⁴-1]

Description#

Description#

If the size of logs created by a DML statement becomes greater than the number of bytes specified in this property, the corresponding transaction is aborted and an error is returned.

This property is used to prevent unusual increases in system load attributable to large volume batch tasks that result from the user’s carelessness.

Because the log size has no limit if this property is set to 0, logs can be used without limit when records are updated. This property can be changed using the ALTER SYSTEM or ALTER SESSION statement when Altibase is running.

SERIAL_EXECUTE_MODE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single value

Range#

[0, 1]

Description#

This property optimizes the filter in the SCAN PLAN to improve the performance of the filter. At this time, it is optimized only for simple filter, and whether it is optimized can be checked in PLAN TREE.

0: Not optimized

1: Optimized

Session Properties#

Session-related properties define the rules for communication between clients and the database server when Altibase is run in a client-server configuration. They are as follows:

CM_DISCONN_DETECT_TIME (Unit: second)#

Data Type#

Unsigned Integer

Default Value#

3

Attributes#

Read-Only, Single Value

Range#

[1, 2³²-1]

Description#

This property specifies the maximum size of the “listen queue” when TCP/IP or UNIX domain protocol is used for communication between a client and Altibase.

MAX_STATEMENTS_PER_SESSION#

Data Type#

Unsigned Integer

Default#

1024

Attributes#

Read-Write, Single Value

Range#

[1, 65535]

Description#

This property specifies the maximum number of statements that can be executed in a session.

This property value can be modified with the ALTER SESSION or ALTER SYSTEM statement while Altibase is running.

NET_CONN_IP_STACK#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Only, Single Value

Range#

[0, 1, 2]

Description#

This property specifies the Internet Protocol Stack to be used when creating sockets on the server side for communication between the client and the server via TCP/IP.

0: An Internet Protocol Stack supporting only IPv4 will be used.

1: A dual stack (Internet Protocol Stack supporting both IPv4 and IPv6) will be used.

2: An Internet Protocol Stack supporting only IPv6 will be used.

NLS_COMP#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Only, Single Value

Range#

[0, 1]

Description#

When a database is created, it cannot be guaranteed that the sequence of characters in the character set specified by NLS_USE is the same as in a dictionary for the language of the country in question.

If this property is set to 1, character comparisons are performed based on the order in which the words in that language appear in a dictionary. If this property is set to 0, character comparisons are performed based on the binary values of the characters.

This is supported only when the database character set is set to Korean (KSC-5601 complete and MS extended complete) because the system currently supports Korean only.

NLS_CURRENCY#

Data Type#

String

Default Value#

Determined by the value of NLS_TERRITORY

Attributes#

Read-Write, Single Value

Range#

Character string, maximum10 bytes

Description#

This property specifies the currency symbol. The value for this property is used to display the local currency symbol with the L number format. This property value cannot begin with +, -, <, > signs.

While Altibase is running, this property value can be modified with the ALTER SESSION statement as below:

ALTER SESSION SET NLS_CURRENCY = '$';

Note: In order to display the Arabic currency symbol properly, the client application program(or shell/editor) must support the display of Arabic characters.

NLS_ISO_CURRENCY#

Data Type#

String

Default Value#

Determined by the value of NLS_TERRITORY.

Attributes#

Read-Write, Single Value

Range#

Value that exists in the V$NLS_TERRITORY performance view.

Description#

This property specifies the ISO currency symbol. The value of this property is used with the C number format to display the international currency symbol. The value of this property is limited to the value(territory) that exists in the V$NLS_TERRITORY performance view.

While Altibase is running, this property value can be modified with the ALTER SESSION statement as below:

ALTER SESSION SET NLS_ISO_CURRENCY = America;

NLS_NCHAR_CONV_EXCP#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

When NCHAR type data are converted to another character set, data loss can occur. In such cases, this property determines whether to raise an error or to continue converting the data despite the possibility of data loss.

This property raises an error only when data conversion is performed on the server; it doesn’t apply to conversion performed on clients.

This property can be changed using the ALTER SESSION statement while Altibase is running.

0: FALSE (Do not raise an error.)

1: TRUE

NLS_NCHAR_LITERAL_REPLACE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

By default, clients convert an entire query string to the database character set before sending the data to the database. This behavior can be prevented for a given string literal by setting this property to 1 and placing the "N" character in front of the string literal.

A property setting of 1 instructs the client to search for the "N" character in front of every string literal. If the "N" character is found, the client sends the string to the database without converting it to the database character set. This is useful when it is desired to use NCHAR type data that are encoded differently from the database character set.

This property can be changed using the ALTER SESSION statement while Altibase is running.

0: convert all strings to the database character set without checking for the "N" character

1: do not convert strings that are preceded by the "N" character to the database character set

Note: Setting this property to 1 can be expensive in terms of usage of client resources.

NLS_NUMERIC_CHARACTERS#

Data Type#

String

Default Value#

Determined by the value of NLS_TERRITORY.

Attributes#

Read-Write, Single Value

Range#

None

Description#

This property specifies the decimal character and the group separator. The group separator is used to display numbers in thousands and generally uses a comma(,). The decimal character generally uses a period(.).This property value cannot begin with +, -, <, > signs.

Of a character string specified for this property, only the first two characters are set as decimal characters; the group separator and the rest are ignored.

While Altibase is running, this property value can be modified with the ALTER SESSION statement as below:

ALTER SESSION SET NLS_NUMERIC_CHARACTERS='.,';

NLS_TERRITORY#

Data Type#

String

Default Value#

KOREA

Attributes#

Read-Write, Single Value

Range#

Value that exists in the V$NLS_TERRITORY performance view

Description#

This property specifies the name of the territory. Values of the NLS_NUMERIC_CHARACTER, NLS_CURRENCY, NLS_ISO_CURRENCY properties are automatically modified according to the territory set for this property. Territory names available for specification of this property can be checked by querying the V$NLS_TERRITORY performance view.

While Altibase is running, this property value can be modified with the ALTER SESSION statement as below. Territory names do not distinguish upper or lower class, and apostrophes(‘) can be used.

ALTER SESSION SET NLS_TERRITORY = America;
or
ALTER SESSION SET NLS_TERRITORY = 'America';

This property can be modified using the ALTER SESSION statement while Altibase is running.

UNIXDOMAIN_FILEPATH#

Data Type#

String

Default Value#

\$ALTIBASE_HOME/trc/cm-unix

Attributes#

Read-Only, Single Value

Range#

None

Description#

This property is a socket file created for Altibase server to connect with a client through the Unix domain.

If the server is driven, the basic socket file is created under $ALTIBASE_HOME/trc directory, and it should be ensured that the file is not deleted.

USE_MEMORY_POOL#

Data Type#

Unsigned Integer

Data Type#

Unsigned Integer

Default Value#

10

Attributes#

Read-Write, Single Value

Attributes#

[0, 10000]

Default Value#

The USER_LOCK_REQUEST_LIMIT sets number of times the user lock that one session can request. The value of this property can be modified through the ALTER SYSTEM statement during the operation of Altibase.

USER_LOCK_REQUEST_TIMEOUT (Unit: second)#

Data Type#

Unsigned Integer

Default value#

10

Attributes#

Read-Write, Single Value

Range#

[0, 2³²-1]

Description#

The USER_LOCK_REQUEST_TIMEOUT establishes the maximum waiting time until the user lock is obtained in a session.

The value of this property can be modified through the ALTER SYSTEM statement during the operation of Altibase.

XA_HEURISTIC_COMPLETE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Only, Single Value

Range#

[0, 2]

Description#

In a distributed transaction environment, Two-Phase Commit Protocol (XA) is used. While a transaction is underway, after a Prepare command has been received from the global transaction coordinator, if for some reason a COMMIT or ROLLBACK command does not arrive for a long time, Altibase will keep the transaction active for a long time, which will negatively affect database performance.

To prevent this, Altibase terminates the entire transaction if it has been in a PREPARE (or IN_DOUBT) state beyond a certain period of time. In such cases, this property determines whether to use COMMIT or ROLLBACK to terminate the transaction.

Altibase waits for the amount of time specified with the XA_INDOUBT_TX_TIMEOUT property before cancelling a transaction in this way. If the value of XA_HEURISTIC_COMPLETE is 0, which is the default, nothing will be done; if it is 1, the transaction will be committed, and if it is 2, the transaction will be rolled back.

Time-out Properties#

BLOCK_ALL_TX_TIME_OUT (Unit: second)#

Data Type#

Unsigned Integer

Default Value#

3

Attributes#

Read-Write, Single Value

Range#

[0, 2³²-1]

Description#

This property can be changed using the ALTER SYSTEM or ALTER SESSION statement while Altibase is running.

IDLE_TIMEOUT (Unit: second)#

Data Type#

Unsigned Integer

Even if this value is set to 1, indicating auto-commit, when the server is started, this property can be changed for individual sessions. For example, if ALTER SESSION SET AUTOCOMMIT = FALSE (non-autocommit) is executed from a client, the user must explicitly specify whether to commit or rollback any transactions that occur for the remainder of the session.

This property can be changed using the ALTER SYSTEM statement while Altibase is running.

ISOLATION_LEVEL#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Only, Single Value

Range#

[0, 3]

Description#

This property specifies the transaction isolation level. When a single transaction searches the same table multiple times, the result varies depending on the isolation level.

For more information about transaction isolation levels, please refer to the Altibase Administrator’s Manual.

Isolation Level	Characteristics
0 (Committed Read)	This is the default mode of Altibase. This isolation level guarantees that previously read data that have been modified by another transaction will reflect the changes of that other transaction. When a SELECT transaction reads data one time and then reads the data again, if another transaction simultaneously executes and commits an INSERT or DELETE statement, due to this change, it is possible for a new row to be found, or for a previously found row to have disappeared.
1 (Repeatable Read)	This isolation level guarantees that the contents of a row will be the same upon repeated reads by the same transaction.This isolation level places a lock on a row once it has been read. Therefore, when the table is subsequently read, previously read rows will not change or disappear, but it is possible for new rows to appear.
2 (No Phantom)	This isolation level guarantees identical results for repeated reads.

TRANSACTION_TABLE_SIZE (Unit: Transaction count)#

Data Type#

Unsigned Integer

Default Value#

1024

Attributes#

Read-Only, Single Value

Range#

[16,16384]

Description#

The number of transactions which can be simultaneously created during the Altibase service is specifiable when creating a database, and memory for such process is allocated in advance.

This property specifies how many copies of the archive log file⁹ are to be kept by the Altibase server. After this property has been specified, copies of newly archived log files are kept.

[⁹] Multiplexing archive log files

This feature copies the archive log files to a separate disk to prepare for the event of damage to the original archive log files.

The ARCHIVE_MULTIPLEX_COUNT and ARCHIVE_MULTIPLEX_DIR properties can be specified while the server is shutdown.

ARCHIVE_MULTIPLEX_DIR#

Data Type#

String

Default Value#

""

Attributes#

Read-Only, Multiple Value

Range#

None

Description#

This property specifies the path for copies of the archive log file. The number of values specified in the ARCHIVE_MULTIPLEX_DIR properties must be equal to the value specified in the ARCHIVE_MULTIPLEX_COUNT property. It is recommended to set each path to a separate disk.

ARCHIVE_THREAD_AUTOSTART#

Data Type#

Unsigned Integer

Default Value#

1

Attributes#

Read-Only, Single Value

Range#

[0, 1]

Description#

This property specifies whether to activate the archivelog thread, which periodically performs archive log file backups. If this property is 1, the archivelog thread is activated.

After the archivelog thread has been suspended due to insufficient disk space in the backup directory, this property is used to restart the thread automatically after sufficient disk space is secured.

CHECKPOINT_ENABLED#

Data Type#

Unsigned Integer

Default Value#

1

Attributes#

Read-Only, Single Value

Range#

[0, 1]

Description#

This property specifies whether checkpointing is enabled (“ON”) or disabled (“OFF”).

0: OFF

1: ON

When this value is 0 (“OFF”), the checkpoint thread cannot be started, and additionally it cannot operate the checkpoint interval specified by CHECKPOINT_INTERVAL_IN_SEC and CHECKPOINT_INTERVAL_IN_LOG. However, the user can perform checkpointing manually.

CHECKPOINT_INTERVAL_IN_LOG#

Data Type#

Unsigned Integer

Default Value#

10

Attributes#

Read-Write, Single Value

Range#

[1, 2³²-1]

Description#

This property defines the checkpoint interval based on the log file creation count. In other words, after the log files have been replaced the number of times specified using this property, checkpointing will be automatically executed. When checkpointing is requested based on this property, it may be impossible to execute, either because checkpointing is already underway, or for some other reason.

In such cases, checkpointing is not initiated immediately again after the checkpointing that is already underway has finished; instead, the current checkpointing request is canceled. Therefore, the next checkpointing request will occur when the number of log files reaches the value set in this property.

This property can be changed using the ALTER SYSTEM statement while Altibase is running.

CHECKPOINT_INTERVAL_IN_SEC (Unit: second)#

Data Type#

Unsigned Integer

Default Value#

6000

Attributes#

Read-Write, Single Value

Range#

[3, 2592000]

Description#

This property specifies the checkpoint interval in seconds.

This property can be changed using the ALTER SYSTEM statement while Altibase is running.

COMMIT_WRITE_WAIT_MODE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

This property specifies whether to wait until logs have been written to log files when committing transactions. In Altibase, the default is not to wait, in the interests of better performance.

This property determines the log buffer type. If it is set to 0, the OS kernel log buffer is used. If it is set to 1, the process memory log buffer is used.

This property cannot be changed while the system is running.

LOG_MULTIPLEX_COUNT#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Only, Single Value

Range#

[0, 10]

Description#

This property specifies how many copies of the log file¹⁰ are to be kept by the Altibase server. Whenever original log files are created or dropped, the copies of log files are also simultaneously created or dropped.

[¹⁰] Multiplexing Log Files

This feature copies the log files to which all changes of the database have been written, to a separate disk to prepare for the event of damage to the original log files.

The LOG_MULTIPLEX_COUNT and LOG_MULTIPLEX_DIR properties can be specified while the server is shutdown.

LOG_MULTIPLEX_DIR#

Data Type#

String

[0, 100]

Description#

This is a property which sets up available thresholds for use in memory database after the snapshot settings (BEGIN SNAPSHOT).

The percentage of the MEM_MAX_DB_SIZE property which is currently being used by memory is verified, and if it exceeds the specified threshold, the snapshot is automatically stopped.

SNAPSHOT_DISK_UNDO_THRESHOLD (Unit: percentage)

Data Type#

Unsigned Integer

Default Value#

80

Attributes#

Read-Write, Single Value

Range#

[0, 100]

Description#

This property specifies thresholds usable in disk after the snapshot settings (BEGIN SNAPSHOT).

It verifies what percentage of the SYS_UNDO_FILE_MAX_SIZE property has been used by the disk undo tablespace up to now, and if it exceeds specified threshold, the snapshot is automatically stopped.

Replication Properties#

The following parameters pertain to database replication. For more information about database replication, please refer to the Getting Started Guide and to the Replication User's Manual.

REPLICATION_ACK_XLOG_COUNT#

Data Type#

Unsigned Integer

Default Value#

100

Attributes#

Read-Write, Single Value

Range#

[0, 2³²-1]

Description#

This property indicates the frequency with which the Receiver thread sends ACK to the Sender thread.

The Receiver thread receives XLogs and replays them one by one. When the number of replayed XLogs exceeds the value specified here, the Receiver thread sends ACK to the Sender thread.

If this value is set too low, the Receiver thread sends ACK too often, leading to reduced performance.

If it is set too high, the amount of time that the Sender thread waits for ACK can increase excessively, and may be treated as a network fault. In addition, if the Sender thread does not receive ACK for an extended time, the replication restart SN is not updated, and thus the Sender thread will start over from the most recent log record if checkpointing occurs, resulting in the deletion of unreplicated logs.

REPLICATION_ALLOW_DUPLICATE_HOSTS#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

This property specifies whether or not to allow replication objects to set duplicate values for the IP address and port number of the remote server.

0: Disallowed

1: Allowed

REPLICATION_BEFORE_IMAGE_LOG_ENABLE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

If the "before image" of the replication Receiver differs from the "before image" of the XLog received from the Sender, it is possible for data conflict to occur.

With this property, the "before image" of the replication receiver can be stored in the trace log to enable the user to check which data conflicted.

0: Disables trace logging

1: Enables trace logging

This property can be changed using the ALTER SYSTEM statement while Altibase is running.

REPLICATION_COMMIT_WRITE_WAIT_MODE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

This property specifies whether to allow DDL statements to be executed on replication target tables. If this property is set to 1, DDL statements can be executed on replication target tables.

Before executing DDL statements, if the replication property of a transaction in the current session is set to a value other than NONE, the Sender thread can be made aware of the execution of DDL statements.

For a list of DDL statements permitted during replication and other restrictions, please refer to the Replication Manual.

This property can be changed using the ALTER SYSTEM statement while Altibase is running.

REPLICATION_DDL_ENABLE_LEVEL#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

This property determines the range of DDL statements that can be used for the replication target table. To use this property, the value of the REPLICATION_DDL_ENABLE has to be set to 1. The following DDL statement is allowed according to the REPLICATION_DDL_ENABLE_LEVEL value.

REPLICATION_DDL_ENABLE_LEVEL = 0

ALTER TABLE table_name ADD COLUMN ( column_name DATA_TYPE );

ALTER TABLE table_name DROP COLUMN column_name;

ALTER TABLE table_name ALTER COLUMN column_name SET DEFAULT

ALTER TABLE table_name ALTER COLUMN column_name DROP DEFAULT

ALTER TABLE table_name TRUNCATE PARTITION

TRUNCATE TABLE table_name;

CREATE INDEX index_name ON table_name ( column_name );

DROP INDEX index_name; -- for Normal Index

REPLICATION_DDL_ENABLE_LEVEL = 1

ALTER TABLE table_name ADD COLUMN ( column_name DATA_TYPE NOT NULL );

ALTER TABLE table_name ADD COLUMN ( column_name DATA_TYPE UNIQUE );

ALTER TABLE table_name ALTER COLUMN ( column_name NOT NULL );

ALTER TABLE table_name ALTER COLUMN ( column_name NULL );

ALTER TABLE table_name MODIFY COLUMN ( column_name DATA_TYPE );

ALTER TABLE table_name MODIFY COLUMN ( column_name NULL );

ALTER TABLE table_name MODIFY COLUMN ( column_name NOT NULL );

ALTER TABLE table_name DROP COLUMN column_name; ( NOT NULL, NULL, Unique, function-base index can also be deleted. )

ALTER TABLE table_name ADD CONSTRAINT constraint_name UNIQUE ( column_name );

ALTER TABLE table_name ADD CONSTRAINT constraint_name UNIQUE ( column_name ) LOCAL;

ALTER TABLE table_name DROP CONSTRAINT constraint_name; ( Unique, Local Unique )

CREATE UNIQUE INDEX index_name ON table_name ( column_name );

CREATE INDEX index_name ON table_name ( expression );

DROP INDEX index_name; ( unique, function-base indexes can be deleted. )

REPLICATION_DDL_SYNC#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

Description#

When replication is performed in eager mode, this property can set the number of times the replication Receiver is to attempt data replication.

If this value is set to 5 and an Xlog replication error occurs, the replication Receiver attempts replication up to 5 times, and forcefully terminates the Altibase server if the last attempt fails.

If the GAPLESS option is enabled, the replication sender allows a replication gap for as long as the value (unit: microseconds) set for the REPLICATION_GAPLESS_ALLOW_TIME property. The replication sender delays transaction commits if it anticipates the replication gap to still exist after the amount of time set for this property.

For example, if the REPLICATION_GAPLESS_ALLOW_TIME property is set to 5 and the sender sends 1,000 XLogs per second, a replication gap of 5,000 XLogs is allowed. If the current replication gap consists of 10,000 XLogs, this means that transaction commits must be delayed for five microseconds, since 5,000 XLogs have exceeded the limit.

If the REPLICATION_GAPLESS_ALLOW_TIME property is set to 0, this means that no replication gaps are allowed; transactions will be committed only after replication gaps are dissolved.

The value of this property can be altered using the ALTER SYSTEM statement while Altibase is running.

REPLICATION_GAPLESS_MAX_WAIT_TIME (Unit: microsecond)#

Data Type#

Unsigned Integer

Default Value#

10,000,000

Attributes#

Read-Write, Single Value

Range#

[0, 2³²-1]

Description#

Description#

This property specifies the number of failed connection attempts to make before determining that a failure has occurred in a replication environment. Thus, the maximum time that can pass before it is determined that a host has failed can be calculated by multiplying REPLICATION_HBT_DETECT_TIME * REPLICATION_HBT_DETECT_HIGHWATER_MARK.

In other words, if the HeartBeat thread (see below) fails to connect for 30 seconds (i.e. 5 attempts * 6 seconds, the default values for each of the above properties), it will be handled as a failure.

This property can be changed using the ALTER SYSTEM statement while Altibase is running.

REPLICATION_HBT_DETECT_TIME (Unit: second)#

Data Type#

Unsigned Integer

Data Type#

Unsigned Integer

Default Value#

600

Attributes#

Read-Only, Single Value

Range#

[0, 2³²-1]

This property specifies the maximum size of the “listen queue” when TCP/IP is used for communication between a Sender thread and an Altibase server that maintains a Receiver thread.

REPLICATION_MAX_LOGFILE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 65535]

Description#

Description#

This property, which is used by both the Sender thread and the Receiver thread, specifies the maximum amount of time, in seconds, to wait for a message from the Receiver or Sender thread, respectively.

In the case where the Sender thread has waited for a response from the Receiver thread for the maximum amount of time specified here, the Sender thread will enter into sleep mode for the amount of time specified using the REPLICATION_SENDER_SLEEP_TIMEOUT property before again attempting to connect to the Receiver thread. In this case, the existing socket is closed and a new socket is created for the new connection attempt.

This property also specifies the maximum time that the Receiver thread waits for a message from a Sender thread. If the specified amount of time has passed, the Receiver thread is automatically terminated, and a new Receiver thread will be created when the Sender thread sends a message.

This property can be changed using the ALTER SYSTEM statement while Altibase is running.

REPLICATION_RECEIVER_APPLIER_ASSIGN_MODE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

REPLICATION_RECEIVER_APPLIER_ASSIGN_MODE

Range#

[0, 1]

Description#

The REPLICATION_RECEIVER_APPLIER_ASSIGN_MODE property sets the mode in which the replication sender is to assign XLogs to the applier.

0: Transaction Count Mode

1: XLog Count Mode

If the REPLICATION_RECEIVER_APPLIER_ASSIGN_MODE property is set to 0, XLogs are assigned to the applier with the least number of transactions.

If the REPLICATION_RECEIVER_APPLIER_ASSIGN_MODE property is set to 1, XLogs are assigned to the applier with the least amount of XLogs.

The value of this property can be altered using the ALTER SYSTEM statement while Altibase is running.

REPLICATION_RECEIVER_APPLIER_QUEUE_SIZE#

Data Type#

Unsigned Integer

Default Value#

20

Attributes#

Read-Write, Single Value

Range#

[2, 2³²-1]

Description#

The REPLICATION_RECEIVER_APPLIER_QUEUE_SIZE sets the maximum number of XLogs that the sender is allowed to be passed to the queue for applier threads.

Although a large value for the REPLICATION_RECEIVER_APPLIER_QUEUE_SIZE property means that a large number of XLogs will be passed to the applier, memory usage increases because XLogs are queued. The user is recommended to set the REPLICATION_RECEIVER_APPLIER_QUEUE_SIZE property to twice as much as the number of appliers.

The value of this property can be altered using the ALTER SYSTEM statement while Altibase is running.

REPLICATION_RECOVERY_MAX_LOGFILE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 2³²–1]

Description#

This property specifies the maximum number of log files that are not deleted, based on a Restart Redo Point, for data recovery using replication.

In order to recover data at the time of replication, the local server does not delete logs that have not been flushed to disk on remote servers. Even if checkpointing takes place at this time, because the log files cannot be deleted, the number of log files on the local server will continue to increase and this can ultimately lead to a disk full error.

Thus, if the maximum log file count in the recovery options is exceeded when checkpointing occurs, replication-based recovery is aborted and the log files are deleted. Then, replication starts over.

If this property is set to 0 or replication runs in eager mode, this function is not used. Because log files are deleted when checkpointing occurs, the values of CHECKPOINT_INTERVAL_IN_SEC and CHECKPOINT_IN_LOG should be considered together.

REPLICATION_RECOVERY_MAX_TIME (Unit: second)#

Data Type#

Unsigned Integer

Default Value#

2³²–1

Attributes#

Read-Only, Single Value

Range#

[0, 2³²–1]

Description#

If the number of seconds specified using this property is exceeded while the replication module is performing recovery, recovery is stopped and service is provided in the state in which recovery has been performed up to that point.

If this property is set to 0, replication-based recovery is not performed.

Before replication-based data recovery is completed, Altibase will not be able to proceed to the service stage, and service may be delayed.

REPLICATION_SENDER_AUTO_START#

Data Type#

Unsigned Integer

Default Value#

1

Attributes#

Read-Only, Single Value

Range#

[0, 1]

Description#

If a replication object which has not been stopped at the termination of the previous Altibase server exists, this replication object is automatically started by default when the server restarts.

If this value is set to 0, a replication object can be prevented from automatically starting.

REPLICATION_SENDER_COMPRESS_XLOG#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

Description#

This property indicates the sleep time, in microseconds, when there are no more logs to be read by the Sender thread. Because certain platforms ignore short Sleep time values, a suitable value must be specified. The value specified here is used in conjunction with REPLICATION_KEEP_ALIVE_CNT to determine when to send KEEP_ALIVE.

REPLICATION_SENDER_SLEEP_TIMEOUT (Unit: second)#

Data Type#

Unsigned Integer

Default Value#

60

Attributes#

Read-Write, Single Value

Range#

[0, 2592000]

Description#

This property specifies the number of microseconds that a replication Sender thread that is in an error state must sleep before trying again.

This property can be changed using the ALTER SYSTEM statement while Altibase is running.

REPLICATION_SENDER_START_AFTER_GIVING_UP#

Data Type#

Unsigned Integer

Default Value#

1

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

This property determines how replication proceeds after replication has been suspended due to the number of accumulated log files preceding the Restart Redo Point exceeding the value of the REPLICATION_MAX_LOGFILE property.

If this value is set to 0, the replication restart SN (which is stored in the XSN column in the SYS_REPLICATIONS_ meta table) is reinitialized (set to -1), and replication is suspended. Additionally, the value of the IS_STARTED column in the SYS_REPLICATIONS_ meta table is set to 0.

If this value is set to 1, the replication restart SN is set to the last generated sequence number in the current log file, and replication is performed starting from this new restart SN.

REPLICATION_SERVER_FAILBACK_MAX_TIME#

Data Type#

Unsigned Integer

Default Value#

2³²-1

Attributes#

Read-Only, Single Value

Range#

[0, 2³²-1]

Description#

In EAGER mode replication, when a server that was terminated abnormally is restarted, it resumes providing service only after it has synchronized its data with the data on another (i.e. the remote) server. At this time, if the process of applying the logs from the other server on the server that experienced the fault takes longer than the number of seconds specified using this property, the server that experienced the fault gives up waiting for synchronization to complete.

REPLICATION_SQL_APPLY_ENABLE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Only, Single Value

Range#

[0, 1]

Description#

This property configures how to synchronize inconsistent data between the local and remote servers during the replication.

0: Replication works using XLog. At this time, if the meta information is different, a Handshaking error occurs.
1: If replication is performed under the following conditions, XLog is converted into a SQL statement and reflected in the replicated table.
Column information
If the data types are different. If sizes, precisions, and scales are different.
Constraints
If the check constraints are different.

If Not Null constraints are different.

If any of the other meta information contains a LOB column.

Indexes
If a unique index or function-based index consists of columns to be replicated and not to be replicated
If the configuration information for the unique index is different
If the configuration information for the function-based index is different

REPLICATION_SYNC_APPLY_METHOD#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Only, Single Value

Range#

[0, 1]

Description#

This property configures how to synchronize inconsistent data between the local and remote servers during the replication.

0: Normal Insert
1: Direct-Path Insert

In an Active-Active replication environment, if this property is set to 1 and a TIMESTAMP column exists in a given replication target table, then the TIMESTAMP-based resolution scheme is used to resolve any data conflicts that occur in that table.

However, even if a TIMESTAMP column exists in a replication target table, if this value has been set to 0, some other conflict resolution scheme is used.

For more detailed information about TIMESTAMP-based resolution and data conflicts, please refer to the Altibase Replication Manual.

This property can be changed using the ALTER SYSTEM statement while Altibase is running.

REPLICATION_TRANSACTION_POOL_SIZE#

Data Type#

Unsigned Integer

Default Value#

2

Attributes#

Read-Write, Single Value

Range#

[0, 2³²-1]

Description#

Replication receivers use transactions when copying data and create respective transaction pools - wherein transactions can be created in advance for use - for performance improvement. This property specifies the number of transactions that are to be created in advance in transaction pools.

If the number of transactions existing in pools falls short, the replication receiver will create new transactions and use them. The transactions thus created are returned to pools after use; if the number of transactions existing at that time is larger than the value specified in this property, the transactions are immediately freed, instead of being returned.

If set to an excessively large value, it can constrain the number of normal transactions; therefore, an appropriate number of transactions must be specified. This property permits the maximum value of 2³²-1; however, the actual maximum value is identical to the value specified in the property of TRANSACTION_TABLE_SIZE. If the user specifies this value to be larger than the value of TRANSACTION_TABLE_SIZE, the value of this property will be internally set as the value of the TRANSACTION_TABLE_SIZE.

This property value can be changed while Altibase is running; however, transaction pools are initialized at the creation of replication receiver threads and replication must be restarted for the modified property values to be applied.

This property value can be changed using the ALTER SYSTEM statement while Altibase is running.

REPLICATION_UPDATE_REPLACE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

This property specifies whether to keep updated contents if an update conflict occurs during replication. If this value has been set to 0, the update will not be committed, and the data conflict will be handled as an error, whereas if this value has been set to 1, the data conflict will be ignored and the update will be committed.

This property can be changed using the ALTER SYSTEM statement while Altibase is running.

Network and Security Properties#

IB_CONCHKSPIN#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Only, Single Value

Range#

[0, 2147483]

Data Type#

Unsigned Integer

Default Value#

1

Attributes#

Read-Only, Single Value

Range#

[0, 1]

Description#

Sets whether or not to send a trap when a utrans timeout occurs.

0: Does not raise a trap.

1: Raises a trap.

For more detailed information, please refer to altiPropertyAlarmUtransTimeout in the SNMP Agent Guide.

SNMP_ALARM_SESSION_FAILURE_COUNT#

Data Type#

Unsigned Integer

Default Value#

3

Attributes#

Read-Only, Single Value

Range#

[0, 2³²-1]

Description#

Sets the number of times an error is allowed to continuously occur before a trap is sent. The default value is 3. If the value is 0, a trap is not sent. For more detailed information, please refer to altiPropertyAlarmSessionFailureCount in the SNMP Agent Guide.

SNMP_ENABLE#

Data Type#

Unsigned Integer

Data Type#

Unsigned Integer

Default Value#

1000

Attributes#

Read-Only, Single Value

Range#

[1, 2³²-1]

Description#

This is the communication timeout value.

When Altibase and altisnmpd(Altibase SNMP subagent) communicate, the application waits for as many milliseconds as specified for this property.

SNMP_SEND_TIMEOUT (Unit: millisecond)#

Data Type#

Unsigned Integer

Default Value#

100

Attributes#

Read-Only, Single Value

Range#

[1, 2³²-1]

Description#

Description#

A list of cipher algorithms available for the server and client to use and negotiate with. Depending on your security policy, you can specify one or more cipher names and separate them by colons. You can check the list at OpenSSL (http://www.openssl.org/) or execute the following command in the shell environment.

$ openssl ciphers

SSL_CIPHER_SUITES#

Default Value#

None

Attribute#

Read-Only, Single Value

Range#

None

Description#

Sets the server private (secret) key path.

An example of this value could be $ALTIBASE_HOME/cert/server- key.pem.

SSL_LOAD_CONFIG#

Data Type#

String

Data Type#

Unsigned Integer

Default Value#

1

Attributes#

Read-Only, Single Value

Range#

[0, 1]

Description#

Altibase server can configure whether or not to communicate with TCP/IP as a communication protocol.

0: Using TCP/IP

1: Not using TCP/IP

Message Logging Properties#

ALL_MSGLOG_FLUSH#

Data Type#

Unsigned Integer

Default Value#

1

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

If this property is set to 1, all database messages are written immediately to disk, whereas if it is set to 0, Altibase writes the messages all at once at regularly scheduled intervals In order to prevent reduced performance attributable to excessive logging, it is recommended that this value be set to 0 for normal operations, and that it be set to 1 when troubleshooting.

COLLECT_DUMP_INFO#

Data Type#

Unsigned Integer

Data Type#

Unsigned Integer

Default Value#

6

Attributes#

Read-Write, Single Value

Range#

[0, 2³²-1]

Description#

Description#

This property specifies the message of service thread to be written to LB_MSGLOG_FILE as follows.

0: not record

[0, 1]

Description#

This is a flag value that indicates whether to write session information regarding all database logon and logoff events to MM_MSGLOG_FILE. Session information includes session ID, user name, IP address, client program PID and other details about the client program.

If this property is set to 0, no messages are written, whereas if it is set to 1, the messages are written.

NETWORK_ERROR_LOG#

Data Type#

Unsigned Integer

Default Value#

1

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

Description#

Description#

This property enables information about the work being conducted by a server and the overall state of the server to be written to a file for later analysis. The user can specify that information is written as desired by suitably combining the following values:

0 : Write nothing
1: Every time a SQL statement is executed, write the executed SQL statement, execution time, execution information, and information about index and disk access. The value for the TIMED_STATISTICS property must be set to 1 to print the proper execution time.
2: Every time a SQL statement is executed, write the BIND parameter(s).
4: Every time a SQL statement is executed, write the execution plan.
8: Write session information (i.e. the data in V\$SESSTAT) every 3 seconds.
16: Write system information (i.e. the data in V$SYSSTAT) every 3 seconds.
32: Write information about memory (i.e. the data in V\$SYSSTAT) every 3 seconds.

For example, if this property is set to 1+4+32=37, then whenever a SQL statement is executed, the execution information and execution plan for the SQL statement is written, and additionally, information about memory is written every 3 seconds.

This file can be converted to a form suitable for analysis using the altiprofile utility. For more information, please refer to the portion of the Altibase Utilities Manual pertaining to the altiprofile utility.

This property can be changed using the ALTER SYSTEM statement while Altibase is running.

QUERY_PROF_LOG_DIR#

Data Type#

String

Default Value#

\$ALTIBASE_HOME/trc

Attributes#

Read-Write, Single Value

Range#

[1, 1024 ]

Description#

Description#

This property specifies the logging level of the trace log of a replication conflict.

The following values are available for specification:

[0, 2³²-1]

Description#

Description#

Description#

Description#

This property determines which of the server XA messages to write to disk. The possible values are as follows:

0: Write only critical XA-related messages

1: Write messages pertaining to XA calls

2: Write messages when XIDs are allocated, freed, etc.

3: Write all message logs related to XA

XA_MSGLOG_RESERVE_SIZE (Unit : byte)#

Data Type#

Unsigned Integer

Default Value#

10 * 1024 * 1024

Attributes#

Read-Only, Single Value

Range#

[0, 2³²-1]

Description#

This property specifies the amount to space to be reserved in advance for storage of the XA message file for the server.

XA_MSGLOG_SIZE#

Data Type#

Unsigned Integer

Default Value#

10 * 1024 * 1024

Attributes#

Read Only, Single Value

Range#

[0, 2³²–1]

Description#

This property specifies the maximum size of XA message files used by the server.

This property specifies the AUTOCOMMIT mode of the remote database. This property is only applied when the DBLINK_GLOBAL_TRANSACTION_LEVEL is set to 0.

0: Autocommit-Off

1: Autocommit-On

DBLINK_GLOBAL_TRANSACTION_LEVEL#

Data Type#

Unsigned Integer

Default Value#

1

Attributes#

Read-Only, Single Value

Range#

[0, 2]

Description#

This property specifies the execution level of the global transaction. When this property is set to 0, the DBLINK_REMOTE_STATEMENT_AUTOCOMMIT property must be set to correspond to the AUTOCOMMIT mode of the remote database.

0: Remote Statement Execution Level.

This level perceives each transaction on servers(local and remote servers) participating in one global transaction as separate transactions, so the transactions must be respectively committed at the local and remote servers in order to commit the global transaction. Even if a global transaction is in this level, a COMMIT performed on the local server does not affect the remote server.

1: Simple Transaction Commit Level.

This level perceives all transactions on servers(local and remote servers) participating in one global transaction as one transaction. Therefore, if a global transaction is committed on a local server, all transactions participating in the global transaction are committed..

2:Two-Phase Commit (2PC) Level.

At this level, the 2PC protocol is supported to ensure transaction consistency of database systems that participating in one global transaction. If a global transaction begins, this property cannot be changed until the end of the transaction.

DBLINK_RECOVERY_MAX_LOGFILE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[1, 2³²-1]

Description#

This property specifies the maximum number of log files that Altibase HDB maintains or distributed transaction recovery when a heterogeneous database system fails during a transaction.

This property specifies the size of the binary audit log file in bytes. This property is used when AUDIT_OUTPUT_METHOD is 0.

The value of this property can be changed using the ALTER SYSTEM statement, as shown below, while Altibase is running.

ALTER SYSTEM SET AUDIT_FILE_SIZE=10000;

However, if the server is in the process of auditing, the changed size applies to files that are created thereafter. For the immediate application of the changed value of this property, restart auditing with the ALTER SYSTEM STOP AUDIT and ALTER SYSTEM START AUDIT statement.

AUDIT_LOG_DIR#

Data Type#

String

Default Value#

\$ALTIBASE_HOME/trc

Attributes#

Read-Write, Multiple Value

Range#

None

Description#

This property specifies the directory in which the binary audit log file is created. This property is used when AUDIT_OUTPUT_METHOD is 0.

The value of this property can be changed using the ALTER SYSTEM statement, as shown below, while Altibase is running.

ALTER SYSTEM SET AUDIT_LOG_DIR='/tmp';

However, if the server is in the process of auditing, the changed size applies to files that are created thereafter. For the immediate application of the changed value of this property, restart auditing with the ALTER SYSTEM STOP AUDIT and ALTER SYSTEM START AUDIT statement.

AUDIT_OUTPUT_METHOD#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Only, Single Value

Range#

[0, 9]

Description#

This property sets the file format for the audit log file. Altibase can store audit information in binary or syslog (syslog is only supported on Linux).

If this property is set to the default value, audit logs are saved in the directory specified for AUDIT_LOG_DIR in binary format. If this property is set to a value between 1~9, logs are stacked in syslog.conf (or rsyslog.conf) using syslog. The syslog message order uses LOG_INFO priority from the syslog.conf file.

0: Stores binary files in the directory specified for AUDIT_LOG_DIR.

1: Stores user facility in /var/log/messages. The file name can be edited at system configuration.

2: Stores to local0 facility, according to user definition.

3: Stores to local1 facility, according to user definition.

4: Stores to local2 facility, according to user definition.

5: Stores to local3 facility, according to user definition.

6: Stores to local4 facility, according to user definition.

7: Stores to local5 facility, according to user definition.

8: Stores to local6 facility, according to user definition.

9: stores to local7 facility, according to user definition.

AUDIT_TAG_NAME_IN_SYSLOG#

Unsigned Integer

CASE_SENSITIVE_PASSWORD#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

This specifies whether or not the database is to distinguish between uppercase and lowercase letters in user passwords. The default value for this property is 0 (case-insensitive), which means that the database treats user passwords as uppercase letters.

0: Does not distinguish between uppercase and lowercase letters (case-insensitive).
1: Distinguishes between uppercase and lowercase letters (case sensitive); however, only if passwords are enclosed in quotation marks (") in the CREATE USER statement. Passwords which are not enclosed in quotation marks are treated as uppercase letters.

This specifies a user-defined CALLBACK function for verifying passwords.

Other Properties#

ACCESS_LIST#

Format#

ACCESS_LIST = operation, address, mask

Range#

operation ::= [PERMIT|DENY]
Indicates whether to allow or deny access by an IP packet that matches a validation rule.
address
Indicates the IP address of the packet to validate. It can be in IPv4 or IPv6 address notation.
mask
If the specified address is in IPv4 address notation, mask specifies that only part of the IP address of a packet, the subnet mask, is to be validated.

If the specified address is in IPv6 address notation, mask gives the length of prefix bits to be compared. An IPv6 address is matched if the specified mask bits of the specified address are equal to the specified mask bits of the originating address of an incoming IP packet.

limit

limit is an optional item. Specifies the maximum number of sessions allowed to access the Altibase server from the accessible IP address range specified in ACCESS_LIST.

If a value is entered in the limit item, limit condition checks are performed on all access requests. Therefore, access is not allowed if the number of access requests from allowed IPs exceeds the limit. If there is no value in the limit item, the limit condition is not checked.

If ACCESS_LIST is added with the ALTER SYSTEM RELOAD ACCESS LIST statement while the Altibase server is running, existing connected sessions are not affected, and the ACCESS_LIST condition is applied only to new connection requests after the change. So when retrieving V$ACCESS_LIST, the CONNECTED value may be greater than the LIMIT value.

Validation Rule#

IF 
BITXOR(BITAND(IP_패킷,mask), BITAND(address,mask)) = 0
THEN  valid
ELSE  invalid

Description#

This property can grant or deny an IP packet attempting to access to Altibase in accordance with an address. By inspecting the IP packet address based upon the specified inspection rules, it can be decided whether or not to allow access. If the IP packet address is corresponding as described in the operation, the access is permitted, but if not, the IP packet is neglected and the next list will be inspected.

If multiple IP packet addresses are specified, the inspection is executed in the order delineated. If there is no address to be matched, the access is allowed.

If the property value of ACCESS_LIST_FILE is described, an external file list defined in the ACCESS_LIST property can be used. The external file can use maximum 1024 lists, but 'ACCESS_LIST=' should be omitted and only the contents should be written out.

Example#

Block packets with the IP address 192.168.1.55 and allow all other packets.

ACCESS_LIST = deny, 192.168.1.55, 255.255.255.255

Allow access to packets from the addresses 192.168.3. and 219.211.253., and block all other packets.

ACCESS_LIST = permit, 192.168.3.0, 255.255.255.0
ACCESS_LIST = permit, 219.211.253.0, 255.255.255.0
ACCESS_LIST = deny ,0.0.0.0, 0.0.0.0

Block all Ipv4 and IPv6 address except for localhost.

ACCESS_LIST = deny, 0.0.0.0, 0.0.0.0
ACCESS_LIST = deny, ::1, 1
ACCESS_LIST = deny, fe80::, 1

Describe the IP address which will be inspected in the external file. Block all IP address except for IPv6 address starting with 192.168.3.* and fe80.

permit, 192.168.3.0, 255.255.255.0
permit, fe80::, 16
deny, 0.0.0.0, 0.0.0.0
deny, ::1, 1
deny, fe80::, 1

Limit the number of sessions accessible from the 192.168.3.17 address to 5.

ACCESS_LIST = permit, 192.168.3.17, 255.255.255.255, 5

ACCESS_LIST_FILE

Data Type#

String

Default Value#

None

Attributes#

Read-Only, Single Value

Range#

None

Description#

This property configures the file path when ACCESS_LIST references an external file path. If the file name and path is not precisely configured, the server will not drive. The absolute path should be specified for an external file path. Refer to the description section of the ACCESS_LIST property for the ACCESS_LIST format.

The list described in ACCESS_LIST property is used if this property is not used.

ADMIN_MODE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

ADMIN_MODE limits the database connection to administrators only.

0: OFF

1: ON

When this property is set to 1, administrator mode is activated, and only the SYS and SYSTEM_ users can connect to the server using the SYSDBA option, and other users will be unable to establish a connection.

This property can be changed using the ALTER SYSTEM statement while Altibase is running.

ARITHMETIC_OPERATION_MODE#

Data Type#

Unsigned Integer

Default Value#

1

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

This property sets the Altibase server to arithmetic operation mode.

0: The server runs in arithmetic operation mode with precision as its priority. The server mainly uses FLOAT or NUMERIC data types to reduce errors from arithmetic operations. The processing speed can be slower than arithmetic operation mode with performance as its priority.

1: The server runs in arithmetic operation mode with performance as its priority. The server mainly uses DOUBLE data types for arithmetic operations to enhance performance; the occurrence of errors is relatively higher.

CHECK_MUTEX_DURATION_TIME_ENABLE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

This property specifies whether to check MUTEX_DURATION_TIME.

This property can be changed using the ALTER SYSTEM statement while Altibase is running.

0: check disable

1: check enable

COERCE_HOST_VAR_IN_SELECT_LIST_TO_VARCHAR#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Only, Single Value

Range#

[0, 32000]

Description#

This property enables host variables to be used in the select target list without CAST operators.

If this property is 1 or greater, the server treats host variables without CAST operators as VARCHAR data types, and the specified value in this property is used as the size (precision) of the VARCHAR data type.

If this property is set to 0, using host variables without CAST operators will cause an error.

DEFAULT_DATE_FORMAT#

Data Type#

String

Default Value#

DD-MON-RRRR

Attributes#

Read-Only, Single Value

Range#

None

Description#

This property sets the default format of DATE type data table columns. If not specified otherwise when SQL statements are executed, DATE type data are input or output according to this setting. This type must specify the formats in which both dates and times are saved. It is also possible to use blanks within double quotation marks, such as "DD MON RRRR".

DEFAULT_DATE_FORMAT = YYYY/MM/DD
iSQL> select sysdate from dual;
SYSDATE
--------------
2008/06/16
1 row selected.

EXEC_DDL_DISABLE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

Generally, after a database is initially created, DML statements are executed much more frequently than DDL statements. Because DDL statements change existing database schema, they must be executed with caution.

The administrator can thus use this property to prevent the execution of DDL statements. When this property is set to 1, DDL statements cannot be executed while Altibase is running, whereas if it is set to 0, DDL statements can be executed.

This property can be changed using the ALTER SYSTEM statement while Altibase is running.

GROUP_CONCAT_PRECISION#

Data Type#

Unsigned Integer

Default Value#

4000

Attributes#

Read-Write, Single Value

Range#

[0, 32000]

Description#

This property specifies the size of the VARCHAR type that the GROUP_CONCAT function returns.

This property can be modified using the ALTER SYSTEM statement while Altibase is running.

JOB_SCHEDULER_ENABLE#

Data Type#

Unsigned Integer

Default Value#

0

Attributes#

Read-Write, Single Value

Range#

[0, 1]

Description#

This controls the operation of the job scheduler. The job scheduler does not operate if the value of the JOB_THREAD_COUNT property is set to 0, even if the value of this property is set to 1.

Read-Write, Single Value

Range#

[0, 1]

Description#

The NO_DATA_FOUND exception is one of the system defined exceptions provided by Altibase's PSM. This exception is raised when the "SELECT ~INTO" statement contained in PSM(stored procedures, functions, triggers) returns no result sets. With the PSM_IGNORE_NO_DATA_FOUND_ERROR property, the user can guard against this exception.

0: When no result set is returned, the NO_DATA_FOUND exception is raised.
1: When no result set is returned, the NO_DATA_FOUND exception is not raised.

The size of usable data varies depending on the value of this property if the scale of parameter is unspecified when creating the stored procedures or if the data size of parameters and return values is not specified in case of creating stored functions.

If the type of parameter or return values is CHAR, NCHAR, NVARCHAR or VARCHAR, and the property value is 1, the size of data type is determined by the values specified in the following properties; however, if the value is set to 0, the size of data type would be 1.

PSM_CHAR_DEFAULT_PRECISION
PSM_NCHAR_UTF8_DEFAULT_PRECISION
PSM_NCHAR_UTF16_DEFAULT_PRECISION
PSM_NVARCHAR_UTF8_DEFAULT_PRECISION
PSM_NVARCHAR_UTF16_DEFAULT_PRECISION
PSM_PARAM_AND_RETURN_WITHOUT_PRECISION_ENABLE
PSM_VARCHAR_DEFAULT_PRECISION

PSM_VARCHAR_DEFAULT_PRECISION#

Data Type#

Unsigned Integer

Default Value#

32000

Attributes#

Read-Only, Single Value

Range#

[1, 65534]

Description#

In case that the size of VARCHAR type is unspecified in the stored procedures or functions, Altibase determines the specified values in the PSM_VARCHAR_DEFAULT_PRECISION property as the size of VARCHAR.

QUERY_STACK_SIZE (Unit: count)#

Data Type#

Unsigned Integer

Default Value#

1024

Range#

Read-Write, Single Value

Range#

[8, 65536]

Description#

This property specifies the size of the stack internally used in the system to process query operations such as comparisons and other operations.

When complicated calculations or stored procedures are used, a stack overflow error may occur. In such cases, the property must be changed to a bigger value.

This parameter must be set according to the application environment. If it is set to a value higher than necessary, memory space will be wasted, so this parameter must be set carefully.

This property can be set in the altibase.properties file, and can be changed using the ALTER SYSTEM or ALTER SESSION statements.

This property can be changed using the ALTER SESSION statement as follows: ALTER SESSION SET STACK SIZE = n;

RECURSION_LEVEL_MAXIMUM#

Data Type#

Unsigned Integer

Default Value#

1000

Attributes#

Read-Write, Single Value

Range#

[5, 2³²-1]

This property specifies the size of the VARCHAR type that the SYS_CONNECT_BY_PATH function returns.

This property can be modified using the ALTER SYSTEM statement while Altibase is running.

This is a property that sets the regular expression mode. Each value indicates the following.

0

Altibase regular expression mode.

POSIX Basic Regular Expression (BRE) and Extended Regular Expression (ERE) are partially supported.

1

PCRE2 compatibility mode.

Supports the regular expression syntax of the Perl Compatible Regular Expressions (PCRE2) library.

This mode can be used when the Altibase server character set is US7ASCII or UTF-8, and there is a difference in syntax from Altibase regular expression mode. For more information, please refer to SQL Reference-Appendix A. Regular Expressions.