INSERT INTO ... SELECT is Slow Using 4K Block Size When Maximum Row Length Exceeds the Block Size (Doc ID 1949291.1)

Last updated on SEPTEMBER 19, 2016

Applies to:

Oracle Database - Enterprise Edition - Version 11.2.0.3 and later
Information in this document applies to any platform.

Symptoms

INSERT INTO ... SELECT command is slow with a 4K block size when compared to an 8K block size.
Elapsed time is longer with increased db block gets , redo size and CPU usage

For example :

4K Table:

 

Cause

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