Real-time statistics for special objects

Objects with certain special characteristics have special implications for real-time statistics.

The following types of objects have specific implications for real-time statistics:

Objects in work file databases

Although you cannot run utilities on objects in the work files databases, Db2 records the NACTIVE, SPACE, and EXTENTS statistics on table spaces in those databases.

Db2 can use partition-by-growth table spaces in work file databases. If you choose to use a partition-by-growth table space in a work file database, you might need to update your real-time statistics programs to work with partition-by-growth statistics. The SYSIBM.SYSTABLESPACESTATS table maintains information about disk storage allocation. This table creates one row for each partition of partition-by-growth table spaces that reside in the WORKFILE database.

DEFINE NO objects

For objects that are created with DEFINE NO, no row is inserted into the real-time statistics table until the object is physically defined.

Read-only or unmodified objects

Db2 does not externalize the NACTIVE, SPACE, or EXTENTS statistics for read-only objects or objects that are not modified