Parallel query wrong result when PX_SEND_BROADCAST_LOCAL is present in the plan

(Doc ID 2372212.1)

Last updated on MARCH 13, 2018

Applies to:

Oracle Database - Enterprise Edition - Version 11.2.0.4 and later
Information in this document applies to any platform.

Symptoms

The incorrect plan looks like:

27 | HASH JOIN BUFFERED| |1 | 1M | 1 | +0 |2 | 0 |
| 28 | VIEW | |2 | 1M | 1 | +0 |2 | 1 |
| 29 | HASH JOIN | |2 | 1M | 1 | +0 | 2 | 1 |
| 30 | PX RECEIVE | |672K| 258| 1 | +0 | 2 | 2 |
| 31 |PX SEND BROADCAST LOCAL| :TQ10000 |672K| 258 | 1 | +0 | 2 | 2 | ----------------->Problematic
| 32 | BUFFER SORT | |2 | | 1 | +0 |3 | 3 |
| 33 | PX BLOCK ITERATOR| |672K| 258 | 1 | +0 |2 | 2 |
| 34 | TABLE ACCESS FULL| TABLE1_N |672K| 258 | 1 | +0 |34 | 2 |
| 35 | PX BLOCK ITERATOR| |76M | 5284 | 1 | +0 | 1 | 1 |
| 36 | TABLE ACCESS FULL| TABLE2_N |76M | 5284 | 1 | +0 | 1 | 1 |
| 37 | PX RECEIVE | |1 |8839 | 1 | +0 | 2 | 1 |
| 38 | PX SEND BROADCAST | :TQ10001 |1 |8839 | 1 | +0 | 2 | 2 |
| 39 | BUFFER SORT | |2 | | 1 | +0 | 3 | 2 |
| 40 | PX BLOCK ITERATOR | |1 | 8839 | 1 | +0 | 2 | 1 |
| 41 | TABLE ACCESS FULL| TABLE3_N |1 | 8839 | 1 | +0 | 1 | 1 |

Cause

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