IBM Db2 Analytics Accelerator for z/OS Version V5.1.0 PTF-6 Release Notes

The HTAP feature (currently only available as technical preview) is only supported with Db2 Version 11. If you plan to use it, you must also install the following PTFs:

The federation feature requires the following PTFs:

Please find information about new functions here.

1. Archiving a table on a second accelerator fails with message AQT10205S (PI85616)
   Affected users

   Users archiving tables to more than one accelerator

   Problem description

   Archive operation fails with error message AQT10205S.

   Problem summary

   A user runs stored procedure SYSPROC.ACCEL_ARCHIVE_TABLES in a high availability environment (HPSS). He wants to archive a table with at least one partition that was rotated to more than one accelerator. The request fails on the second accelerator with error message AQT10205S.

   Problem conclusion

   The problem has been fixed.
2. Archiving and restoring of a table on more than one accelerator may fail with message AQT10402E (PI85619)
   Affected users

   Users of HPSS in high availability environments

   Problem description

   Archive and restore operations fail with error message AQT10402E.

   Problem summary

   Archiving or restoring of a table with a high number of partitions in an high availability environment on more than one accelerator may fail on the second accelerator with error message AQT10402E.

   Problem conclusion

   The problem has been fixed.
3. SYSPROC.ACCEL_ADD_TABLES fails with error message AQT10205S for tables created with an old version of Db2/z (PI87927)
   Affected users

   Users running stored procedure SYSPROC.ACCEL_ADD_TABLES

   Problem description

   SYSPROC.ACCEL_ADD_TABLES fails with error message 'AQT10205S - An internal processing error occurred in the stored procedure. Diagnostic information: An assertion 'numberOfColumns==deps[i].mParentKeyColumns.size()'; failed. Additional info: parent key doesn't match foreign key'

   Problem summary

   The problem occurs

   • if a table with a primary key referential integrity constraint was created with Db2 version 6 or lower and
   • if a further table with a related foreign key was created and
   • if the tables are added to the accelerator.

   Problem conclusion

   The problem has been fixed.
4. Stored procedure dumps are not taken (PI87428)
   Affected users

   Users running stored procedures

   Problem description

   In case a stored procedure encounters a severe issue, it attempts to write a DUMP. The collection of the DUMP fails with message: IEA820I TRANSACTION DUMP REQUESTED BUT NOT TAKEN. '&DS' MUST BE AT END OF DSN TEMPLATE.

   Problem summary

   If a stored procedure attempting to write a dump is not APF-authorized and if the AQTENV-parameter AQT_SYSTEMDUMP_DSN_TEMPLATE has not been set, the following default dump data set name is used: <USERNAME>..DUMP.&JOBNAME..D&YYMMDD..T&HHMMSS..X&DS. The default data set name did not end with a dot causing the dump to fail.

   Problem conclusion

   The problem has been fixed.
5. Description of submenu item 5 of main menu item 3 on IBM Db2 Analytics Accelerator console is misleading
   Affected users

   Users of IBM Db2 Analytics Accelerator console

   Problem description

   The description has been changed to:
   'The Netezza internal workload manager allows maintenance operations, such as loading data, to run with certain priorities. Please set the priority of maintenance operations for the ... subsystem. '

   Problem summary

   The description of submenu item 5 ('Specify the priority of maintenance task') of main menu item 3 ('Run Accelerator Functions') on IBM Db2 Analytics Accelerator console 'Queries are run with the priority that is set in the corresponding System z Workload Manager (WLM) environment. You can set the priority of maintenance operations, such as loading data, analogously for the ... subsystem:' is misleading. The word 'Queries' in this description seems to indicate that this function to adjust the priority for queries, which is not the case.

   Problem conclusion

   The problem has been fixed.
6. A failed attempt to enable incremental updates stops incremental updates for all paired database systems
   Affected users

   Users wanting to enable incemental updates

   Problem description

   Incremental updates for all pairings remain stopped after a failed attempt to enable incremental updates for an additional pairing. They cannot be started again until the attempt to enable incremental updates for the additional pairing is successful.

   Problem summary

   If there is at least one pairing for which incremental updates have been enabled and if for an additional pairing on the same accelerator the attempt to enable incremental updates fails, the incremental update processes for all existing pairings are stopped and are not restarted automatically.

   Problem conclusion

   The problem has been fixed.
7. SYSPROC.ACCEL_ARCHIVE_TABLES does not return when table space name has trailing blanks (PI90094)
   Affected users

   Users running stored procedure SYSPROC.ACCEL_ARCHIVE_TABLES

   Problem description

   Stored procedure SYSPROC.ACCEL_ARCHIVE_TABLES does not return when table space name has trailing blanks.

   Problem summary

   If a table space name of a table to be archived ends with a blank, the SYSPROC.ACCEL_ARCHIVE_TABLES procedure does not detect a partition state correctly and waits indefinitely for a state change.

   Problem conclusion

   The problem has been fixed.
8. Enabling the Continuous Replication feature may result in an error message complaining about the port number (PI90333)
   Affected users

   Users trying to enable Continuous Replication feature

   Problem description

   Enabling Continuous Replication with a port number xxx less than 446 results in error message 'Port xxx is not valid because the port number must be greater than 446 for database system yyy with location name zzz and IP address uuu.'

   Problem conclusion

   The port number limitation for enabling Continuous Replication has been removed.
9. Queries may erroneously result in SQLCODE -904
   Affected users

   Users of accelerated queries

   Problem description

   Queries may erroneously result in SQLCODE -904.

   Problem summary

   When processing queries there could be a rare instance where Db2z sends an unsupported message format to the accelerator. In the following SQLCODE -904 would be issued erroneously.

   Problem conclusion

   The problem has been fixed, the proper DRDA error message is issued.
10. Call home function allows attachments with a size that is rejected by the mail server (PI88003)
    Affected users

    Users of call home function

    Problem description

    The call home function allows attachments of arbitrary size. Mails with these large attachments might be rejected by the mail server.

    Problem conclusion

    The IBM Db2 Analytics Accelerator console contains a new menu entry to enter the maximum size for attachments. It is available from the submenu "Manage 'Call Home'" as menu item "Update maximum trace file size".

For recommendations and considerations concerning migration to IBM Db2 Analytics Accelerator for z/OS Version 5.1.0 read here.

1. IBM Netezza Analytics
   For known issues with the IBM Netezza Analytics stored procedure package in IBM Db2 Analytics Accelerator for z/OS Version 5.1.0, see:

   Known issues with IBM Netezza Analytics for System z for IBM Db2 Analytics Accelerator for z/OS Version 5.1.0

2. Encryption of Data in Motion
   For known issues with the network traffic encryption feature (encryption of data in motion) in IBM Db2 Analytics Accelerator for z/OS Version 5.1.0, see:

   Known Issues with Encryption of Data in Motion in IBM Db2 Analytics Accelerator for z/OS Version 5.1.0

3. Transfer of software update packages from IBM Db2 Analytics Accelerator Studio not possible
   Summary

   IBM Analytics Accelerator Studio does not allow users to transfer packages. A message hints at the fact that a newer version is already installed on the server. If the locale in the IBM Analytics Accelerator Data Studio is set to a value different from English or German, the transfer of software update packages might be blocked in rare cases.

   Solution or workaround

   The problem has been fixed with the stored procedures of IBM Db2 Analytics Accelerator for z/OS Version 5.1.0 maintenance level PTF-1. If you run the software transfer with a previous version of the stored procedures, use the following workaround:

   1. Use US English as the locale for IBM Db2 Analytics Accelerator Studio.
   2. On a Windows system, add '-nl en_US' (without the quotes) to the start command that you find in the properties of the shortcut that launches the application ("Target" field on "Shortcut" tab).

      On a Linux system, open the eclipse.ini file and add the following line:

      -Duser.language=en -Duser.country=US

   3. Save and close the file. Then start the application.
4. If the system utilization is very high, the accelerator might restart automatically to recover from the overload situation
   Summary

   The accelerator goes online again after the recovery. Processes that were ended prematurely by the restart, such as load jobs or queries, must be restarted.
   Example of high system utilization: 30 parallel load threads with tables having 10 partitions

   Solution or workaround

   1. Check the system utilization.
   2. Adjust the system utilization as needed.
   3. Retry failed operations and continue.
5. The execution of an INSERT INTO ... SELECT ... FROM statement in an in-database transformation job might fail
   Summary

   In rare situations, INSERT INTO ... SELECT ... FROM statements in in-database transformation jobs can fail if the system utilization is very high and many processes are run in parallel.

   Solution or workaround

   This is an indication that the system limits were reached. Check the system utilization and adjust it to the capacity of the system.
6. Incremental update processing might stop and restart if the system utilization is very high (many parallel load and query operations). This is indicated by according console messages
   Summary

   If the system utilization is very high, with many processes running in parallel, the processing of incremental updates might stop. Processing resumes after some time and stalled operations are recovered automatically. If "continuous incremental updates" are enabled, tables that are being loaded at the time of the interruption go into the "suspended" state. You must reload such tables to get them back into the incremental update processing queue.

   Solution or workaround

   This is an indication that the system limits were reached. Check the system utilization and adjust it to the capacity of the system.
7. Insertion of integer and decimal values causes failure of IDT jobs
   Summary

   The insertion of integer and decimal values by an INSERT INTO ... VALUES statement might cause a failure of in-database transformation (IDT) jobs.

   For example, the following statement failed during tests:
   CREATE TABLE T1 (CDEC51 DECIMAL(5,1)) IN ACCELERATOR XYZ;
   INSERT INTO T1(CDEC51) VALUES(77247.04-69993);

   Symptoms: SQL codes like the following are returned:

   SQLCODE = -802, SQLSTATE = 22003, DATA EXCEPTION FROM IBM DB2 Analytics Accelerator TOKENS OVERFLOW ACCELERATOR NUMERIC DATA...

   Solution or workaround

   Use only decimal values instead of a mixture of integer and decimal values. The following statement, for example, will be successful:

   INSERT INTO T1(CDEC51) VALUES(77247.04-69993.0)

8. Tables cannot be added if their names contain special characters, such as tabs and newlines
   Summary

   Tables cannot be added if their names contain special characters, such as tabs and newline characters.

   Solution or workaround

   Fix will be delivered in a later release.
9. Large number of accelerator-shadow tables might extend time needed to activate incremental updates
   Summary

   If there is a large number of tables on an accelerator, that is, more than 30000 the activation of incremental updates for these tables might take longer. In this context, it does not matter whether the tables have already been enabled. The extra time needed is relevant if the number of table activations in one request exceeds 10 because this will lead to a premature end of the operation, which in turn leads to an automatic disablement of incremental updates for those tables. You must re-enable and reload such tables.

   Solution or workaround

   Reduce the number of tables that are activated in a single batch job to less than ten (<10).
10. If the system utilization is high, load operations might fail with a message "Failed to start child transaction in session " -LocksharedObjectWait: LockAcquire failed".
    Summary

    Under a high system load, load operations might fail with a message "Failed to start child transaction in session " -LocksharedObjectWait: LockAcquire failed".

    Solution or workaround

    Retry the load operation.
11. ALTER TABLE ALTER PARTITION is not blocked by a partition in PRO State (Db2 V11 only)
    Summary

    A partition can be altered by an ALTER TABLE ALTER PARTITION statement although the partition has been archived by the SYSPROC.ACCEL_ARCHIVE_TABLES stored procedure. Normally, SQLCODE -904 would be returned because the archived partition has been set to the PRO state.

    Solution or workaround

    Because a read-only partition was changed, a following restore operation will probably fail. The problem has been fixed in Db2 V12.

• Use the sample code (for a stored procedure) in the following technote:

  How to store information about accelerated tables in a Db2 for z/OS table

  to retrieve information about your accelerator-shadow tables. This information will be stored in a temporary Db2 table.

• Run a simple SQL query against the replicationStatus and the lastLoadTimestamp columns of this temporary table to identify tables that must be reloaded. Follow the diagram at the end of this note to determine whether a table must be reloaded.

• Immediately after the upgrade to V5.1.0 PTF-6, an automatic conversion of data structures takes place.
• Depending on the total amount of data to be converted, this might take more than 1 hour, during which the Netezza Platform Software (NPS) will be in the "Initializing" state. That is, the NPS cannot process requests.

Support for Db2 12 for z/OS

Please find known issues here.