Database Options

Database options customize and modify database behavior.

• AGGREGATION_PREFERENCE Option
  Controls the choice of algorithms for processing an aggregate.
• ALLOW_SNAPSHOT_VERSIONING Option
  Applies to all base tables in the database (as opposed to RLV-enabled tables only). Restricts table versioning for all base tables to either table-level or row-level snapshot versioning. This option does not apply to the IQ catalog store.
• BASE_TABLES_IN_RLV_STORE Option
  Registers tables in the RLV store, enabling row-level versioning. RLV-enabled tables are eligible for multiple writer concurrent access. You can override this setting at the table level using the CREATE_TABLE statement.
• BLOCKING Option
  Controls the behavior in response to locking conflicts.
• BLOCKING_TIMEOUT Option
  Controls the length of time a transaction waits to obtain a lock.
• ENABLE_ASYNC_IO Option
  Allows a DBA to enable or disable the asynchronous IO used by the RLV persistence log.
• LOG_DEADLOCKS Option
  Controls whether deadlock reporting is turned on or off.
• RV_AUTO_MERGE_EVAL_INTERVAL Option
  This option configures the evaluation period used to determine when an automated merge of the row-level versioned (RLV) and IQ main stores should occur.
• RV_MERGE_NODE_MEMSIZE Option
  An automated merge of the row-level versioned (RLV) store and IQ main stores occurs based on the merge thresholds, including RV_MERGE_NODE_MEMSIZE. When this node threshold is exceeded, a merge will be triggered.
• RV_MERGE_TABLE_MEMPERCENT Option
  An automated merge of the row-level versioned (RLV) store and IQ main stores occurs based on the merge thresholds, including RV_MERGE_TABLE_MEMPERCENT. If this table threshold is exceeded, a merge will be triggered for the specific table.
• RV_MERGE_TABLE_NUMROWS Option
  An automated merge of the row-level versioned (RLV) store and IQ main stores occurs based on the merge thresholds, including RV_MERGE_TABLE_NUMROWS. If this table threshold is exceeded, a merge will be triggered for the specific table.
• RV_RESERVED_DBSPACE_MB Option
  A portion of the RLV store must be reserved for memory used by data structures during critical operations.
• SNAPSHOT_VERSIONING Option
  Applies to RLV-enabled tables only (as opposed to all base tables in the database). Controls whether RLV-enabled tables are accessed using single-writer table-level versioning, or multiple writer row-level versioning. This option does not apply to the IQ catalog store.