DB2 in simple way: what is index only access

The definition in very simple English is ,if all the data being retrieved is present in index, then DB2 satisfy the query without Accessing base table. The index only access in db2 is a key measurement for performance of your SQL Query.

So additional reads of table pages not required,then I/o is reduced, then performance will be increased.

The same you can find in PLAN_TABLE results as

INDEX ONLY: Y

This means Accessing index is enough and no need to access table.

The below five columns you need to refer in PLAN_TABLE

  1. ACCESSTYPE
  2. MATCHCOLS
  3. ACCESSCREATOR
  4. ACCESSNAME
  5. INDEDEX ONLY
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Author: Srini

Experienced software developer. Skills in Development, Coding, Testing and Debugging. Good Data analytic skills (Data Warehousing and BI). Also skills in Mainframe.