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Query Execution is slow in Standby DB When Compared to Primary (Doc ID 2980050.1)

Last updated on NOVEMBER 26, 2023

Applies to:

Oracle Database - Enterprise Edition - Version and later
Information in this document applies to any platform.


Observing performance issues for certain queries in Active Read only Dataguard (ADG) - When select queries are executed through ADG it was taking around more time while the same select query is completing within 30 secs in primary database.

There is a change in the query execution plan, for example:

The query execution plan on primary shows "TABLE ACCESS INMEMORY FULL" on TESTTAB, but ADG plan has "TABLE ACCESS FULL" on the same table.


In-memory option has been enabled for the table, in the primary Database.


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