Author Topic: Recommended DB2 on z/OS Service, V12  (Read 8463 times)

Ed_Arnold

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Re: Recommended DB2 on z/OS Service, V12
« Reply #15 on: March 30, 2022, 11:29:25 AM »
I'm still maintaining this.  Noting that there's been nothing new since my last update.

Ed
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Ed_Arnold

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Re: Recommended DB2 on z/OS Service, V12
« Reply #16 on: June 03, 2022, 08:29:47 AM »
Saw this today and thought it might be of interest:

PH29392: NEW FUNCTION
.
https://www.ibm.com/support/pages/apar/PH29392
.
This APAR introduces NEW Function, for Level 508. This is the Function that affects MQ as well.

From the DB2 V12 documentation:

* Function level 508 (V12R1M508) introduces support for moving tables from deprecated multi-table simple and multi-table segmented table spaces to partition-by-growth universal table spaces (UTS), without taking an outage, to improve application and database operations and performance.
It is the introduction of UTS Tablespaces that affects MQ, because MQ will need to migrate all simple Tablespaces to UTS format.
.
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Ed_Arnold

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CMOD has surfaced the following Db2 APAR
« Reply #17 on: March 12, 2024, 09:50:11 PM »
PH56940: ABEND0C4 RC10 AT DSNXOD3 OFFSET04726 MAY OCCUR FOR THE QUERY USING SINGLE INDEX ACCESS

Error description
ABEND0C4 RC10 AT DSNXOD3 OFFSET04726 MAY OCCUR when explaining
an SQL statement whose access path contains single index access.

KEYWORDS: ABEND0C4 SQLEXPLAIN SQLACCESSPATH
Local fix
Avoid Explain on the impacted SQL statement.
Problem summary
****************************************************************
* USERS AFFECTED:                                              *
* All users of Db2 12 and Db2 13 for z/OS who                  *
* explain queries whose access path contains                   *
* single index access.                                         *
****************************************************************
* PROBLEM DESCRIPTION:                                         *
* ABEND0C4 at DSNXOD3 offset 04726 may                         *
* happen when explaining an SQL                                *
* statement whose access path contains                         *
* single index access.                                         *
* Abend only happens when the accessed                         *
* storage is not available. Otherwise,                         *
* incorrect information may be populated                       *
* into column IBM_SERVICE_DATA of                              *
* PLAN_TABLE.                                                  *
****************************************************************
* RECOMMENDATION:                                              *
* Apply corrective PTF when available                          *
****************************************************************
For example:
EXPLAIN ALL SET QUERYNO = 1 FOR
SELECT C1,C2 FROM T1
WHERE T1.C1 = 100;
Index IX(C1) is chosen to access T1. When populating data into
PLAN_TABLE, an invalid array index zero is used that may result
in ABEND0C4 at DSNXOD3 offset 04726 or incorrect information in
column IBM_SERVICE_DATA of PLAN_TABLE.
Problem conclusion
Db2 has been modified to correctly process the aforementioned
SQL statement.
Additional Keywords ABEND0C4 SQLEXPLAIN SQLINDEX
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Ed_Arnold

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CMOD has surfaced the following Db2 APAR
« Reply #18 on: March 12, 2024, 09:52:30 PM »
PH57851: ABEND0C4 MAY HAPPEN AT DSNXOGP:0AB44 FOR QUERY WITH MULTI-INDEX ACCESS.

Error description
ABEND0C4 may happen at DSNXOGP:0AB44 for query with multi-index
access.
The abend happens during choosing access path for query.

ADDITIONAL SYMPTOMS:
ABEND0C4 MIDX DSNXOGP OFFSET0AB44 OFFSETAB44 0AB44 AB44
Local fix
BYPASS/CIRCUMVENTION:
Please try adding OPTIMIZE FOR 1 ROW to discourage optimizer
from using multi-index.
Problem summary
****************************************************************
* USERS AFFECTED:                                              *
* All users of Db2 12 and Db2 13 for z/OS who                  *
* has queries whose access path contains                       *
* multiple index access.                                       *
****************************************************************
* PROBLEM DESCRIPTION:                                         *
* ABEND0C4 at DSNXOGP offset 0AB44 may                         *
* occur for an SQL statement whose                             *
* access path contains multiple index                          *
* access.                                                      *
****************************************************************
* RECOMMENDATION:                                              *
* Apply corrective PTF when available                          *
****************************************************************
ABEND0C4 at DSNXOGP offset 0AB44 may occur for an SQL statement
whose access path contains multiple index access.
The abend is intermittent depending on the availability of
certain storage.
Problem conclusion
Db2 has been modified to correctly process the aforementioned
SQL statement.
Additional Keywords ABEND0C4 SQLEXPLAIN SQLINDEX MIDX
                    SQLACCESSPATH
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