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Exadata:SQL query returns wrong/non-deterministic results in 19.11 DB. (Doc ID 2866522.1)

Last updated on JUNE 27, 2023

Applies to:

Oracle Exadata Storage Server Software - Version 21.2.8.0.0 and later
Information in this document applies to any platform.

Symptoms

After migrating 19.11 database to Exadata, particular query was found returning wrong/non-deterministic results:
'alter session set "cell_offload_processing"=FALSE;'
' : shows rdbms results without offloading'
COUNT(*)
----------
1903280

'alter session set "cell_offload_processing"=TRUE;'
' : shows that we have problems with cell_offloading'

COUNT(*)
----------
1900343

'alter session set "_kcfis_storageidx_disabled"=TRUE;'
' : see if this is SI-related'

COUNT(*)
----------
1900688

'alter session set "_kcfis_storageidx_diag_mode" = 8;'
': see if this is related to SI copied during rebalance'

COUNT(*)
----------
1899990

'alter session set "_kcfis_storageidx_set_membership_disabled"=TRUE;'
' : see if this is SI membership related'

COUNT(*)
----------
1900117

'alter session set "_kcfis_kept_in_cellfc_enabled"=FALSE;'
' : see if this is FC to keep'

COUNT(*)
----------
1900359

 

//From Exadata DB server IMAGEINFO

Kernel version: 4.14.35-2047.502.5.el7uek.x86_64 #2 SMP Wed Apr 14 15:08:41 PDT 2021 x86_64
Image kernel version: 4.14.35-2047.502.5.el7uek
Image version: 21.2.0.0.0.210429.1
Image activated: 2021-05-23 11:37:52 +0200
Image status: success
Node type: COMPUTE
System partition on device: /dev/mapper/VGExaDb-LVDbSys1

//Exadata Cell version: OSS_21.2.8.0.0_LINUX.X64_220114.1

 

Changes

 DB upgraded to 19.11

Cause

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In this Document
Symptoms
Changes
Cause
Solution
References


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