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Wrong Results When Parallelism Is Used and ORA-600 [15570] listed in the alert.log. (Doc ID 1472485.1)

Last updated on FEBRUARY 20, 2019

Applies to:

Oracle Database - Enterprise Edition - Version 10.2.0.4 to 12cBETA2 [Release 10.2 to 12.1]
Oracle Database Cloud Schema Service - Version N/A and later
Oracle Database Exadata Cloud Machine - Version N/A and later
Oracle Database Exadata Express Cloud Service - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Information in this document applies to any platform.

Symptoms

This issue has been observed on 10.2.0.4 to 11.2.0.3 versions,

When attempting to execute a select query in parallel, wrong results are seen.

Execution Plan (Wrong Results) from 10.2.0.4:
 =============================================
 -----------------------------------------------------------------------------
 | Id |Operation                       |Name           |Rows|  TQ |PQ Distrib|
 -----------------------------------------------------------------------------
 |   0|SELECT STATEMENT                |               |   1|     |          |
 |   1| PX COORDINATOR                 |               |    |     |          |
 |   2|  PX SEND QC (RANDOM)           |:TQ10002       |   1|Q1,02|QC (RAND) |
 |   3|   NESTED LOOPS                 |               |   1|Q1,02|          |
 |   4|    NESTED LOOPS                |               |   1|Q1,02|          |
 |   5|     NESTED LOOPS               |               |   1|Q1,02|          |
 |   6|      BUFFER SORT               |               |    |Q1,02|          |
 |   7|       PX RECEIVE               |               |    |Q1,02|          |
 |   8|        PX SEND BROADCAST       |:TQ10000       |    |     |BROADCAST |
 |*  9|         INDEX RANGE SCAN       |<INDEX_NAME>   |   1|     |          |
 |  10|      SORT UNIQUE               |               |   1|Q1,02|          |
 |  11|       BUFFER SORT              |               |    |Q1,02|          |
 |  12|        PX RECEIVE              |               |   1|Q1,02|          |
 |  13|         PX SEND HASH           |:TQ10001       |   1|Q1,01|HASH      |
 |  14|          PX PARTITION RANGE ALL|               |   1|Q1,01|          |
 |* 15|           INDEX RANGE SCAN     |<INDEX_NAME>   |   1|Q1,01|          |
 |* 16|     INDEX UNIQUE SCAN          |<INDEX_NAME>   |   1|Q1,02|          |
 |  17|    PARTITION RANGE SINGLE      |               |   1|Q1,02|          |
 |* 18|     INDEX RANGE SCAN           |<INDEX_NAME>   |   1|Q1,02|          |
 -----------------------------------------------------------------------------
When parallelism is disabled the correct lines are seen.

Changes

 

Cause

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In this Document
Symptoms
Changes
Cause
Solution
References


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