This setting enables memory overwrite checking at runtime and during roll forward. This check focuses on potential memory overwrites in the buffer pool. When this setting is enabled, the consistency checks will be applied to all index blocks and record blocks.
Note: Memory overwrite checking is performed on record and index write operations only.
When using this option, consider the following:
Index and record block operations are checked prior to before-image note writing and the subsequent database block write. The length of the intended operation is checked to prevent operations that exceed the database block size.
Index block splits are checked during the strategic points in an index block split operation.
Index insert operations are checked during the strategic points of the insertion of a key element.
Enter the option to enable/disable a consistency check:
Choose one of the following settings:
-MemCheck — Enables memory consistency check.
-DbCheck — Enables database consistency check. When this option is enabled, the consistency check is applied to all index blocks and record blocks (except BLOB blocks) in the entire database.
-AreaCheck — Enables area consistency check. When this option is enabled, the consistency check is applied to all index blocks and record blocks (except BLOB blocks) in the specified area.
-IndexCheck — Enables index consistency check. When this option is enabled, the consistency check is applied to all index blocks of the specified index. This check is for index blocks only.
-TableCheck — Enables table consistency check. When this option is enabled, the consistency check is applied to all record blocks (except BLOB blocks) of the specified table. This check is for record blocks only.
The following precedence rules apply when enabling multiple parameters at the same time:
Each option can only be enabled once. For example, the following parameters are invalid: -AreaCheckCustomer Area -AreaCheckOrder Area.
If the -DbCheck option is used with any other options, -DbCheck will have precedence and the consistency check will be applied on the whole database.
-AreaCheck <area name>, -IndexCheck <index name> and -TableCheck <table name> can be used at the same time. The consistency check will be enabled for the superset of these options.