An index is a DB2 object that contains an ordered set of pointers into a table. The index is based on one or many columns in a table and can be created at any time after the target table has been created. It is more efficient to load the table after the indexes have been defined.
An index is used to improve performance and help ensure uniqueness of the columns. Every index occupies its own index space, which consists of one to several LDS VSAM data sets. The index space is always stored in the same database as the target table. When you create the index (index space), you designate its storage group or VSAM catalog for explicit VSAM definitions and buffer pool. If you do not specify a buffer pool or storage group, the index uses the storage group and buffer pool that are designated for the database. An index can be partitioned or simple.
When you select indexes from the Investigator, CA Chorus displays the information necessary to monitor index definitions and plan dependencies.
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