Release Notes
Abstract
This document describes enhancements and fixes in IBM DB2 Analytics Accelerator for z/OS Version 5.1.0, maintenance level PTF-5
Content
Depending on the DB2 version you are using the following DB2-PTFs must be installed:
DB2 Version 10: PTF UI48441 (APAR PI76645)
DB2 Version 11: PTF UI48442 (APAR PI76645)
DB2 Version 12: PTF UI48621 (APAR PI82739)
The new federation feature is only supported with DB2 Version 11. If you plan to use it, you must also install the following DB2-PTF:
DB2 Version 11: PTF UI48595 (APAR PI77826)
The minimum required version of IBM DB2 Analytics Accelerator Studio for this maintenance level is:
6.1.3.201706282249
After an installation of V5.1.0 maintenance level PTF-5, the former method of data organization is re-activated. If the switch back to the former data organization fails, the following message is written to the z/OS system log (SYSLOG) of the LPAR in which the DB2 subsystem or group is located:
How to identify tables that should be reloaded after an installation of V5.1.0 maintenance level PTF-5
What's new
Please find information about new functions here.
Solved problems
- Stored procedure SYSPROC.ACCEL_GET_TABLES_DETAILS returns error message AQT10301EAffected usersAll users of IBM DB2 Analytics Accelerator for z/OS Version 5.1.0Problem descriptionSYSPROC.ACCEL_GET_TABLES_DETAILS fails with an error message similar to: AQT10301E - An error occurred in the DSNWLIR service of your database management system (DBMS). The return code is 8. The reason code is 0x00E60820. Additional diagnostic information: 'error in DB2 command '-ACCESS DB(POULÅÅ92) SP(POULÅÅ1S) MODE(STATS)': DSN9027I -DB2A KEYWORD 'DB' PARAMETER(S) MUST BE ALPHAMERIC DSN9027I -DB2A KEYWORD 'SP' PARAMETER(S) MUST BE ALPHAMERIC DSN9023I -DB2A DSN9SCND '-ACCESS DB' ABNORMAL COMPLETIONProblem summaryThe problem occurs if database or tablespace names for an accelerated table contain characters whose codepoints are different in the 1047 CCSID and the EBCDIC SBCS CCSID set in DSNHDECP.Problem conclusionThe problem has been fixed.
- DSNR035I message in console log while running a load jobAffected usersAll users of IBM DB2 Analytics Accelerator for z/OS Version 5.1.0Problem descriptionMessage DSNR035I appears on the console while loading data into accelerator-shadow tables. The affected object is DSNAQT.UNLOADIDS.Problem summaryThe loading of accelerator-shadow tables requires a unique DB2 sequence number. A lock is held on the corresponding sequence during the load, which causes the DSNR035I messages on the console.Problem conclusionThe problem has been fixed.
- Discrepancy between 'DISK STORAGE IN USE' valuesAffected usersAll users of IBM DB2 Analytics Accelerator for z/OS Version 5.1.0Problem descriptionThe monitoring section in IBM DB2 Analytics Accelerator Studio and the -DISPLAY ACCEL command in DB2 might display different values for 'DISK STORAGE IN USE'. The discrepancy between the values amounts up to 10%.Problem summaryReported values for the use of disk space differ. The difference amounts up to 10 percent.Problem conclusionThe problem has been fixed.
- Load jobs fail with out-of-memory error conditionAffected usersAll users of IBM DB2 Analytics Accelerator for z/OS Version 5.1.0Problem descriptionThe load performance decreases because wrongly triggered reorganization jobs reserve memory blocks. In the worst case, out-of-memory errors occur during load.Problem summaryThe problem occurs when users reload accelerator-shadow tables.Problem conclusionLoad jobs fail less frequently with out-of-memory error condition.
- Load jobs fail with message 'Missing management subscription for subscription XXX.'Affected usersAll users of the incremental update function in IBM DB2 Analytics Accelerator for z/OS Version 4.1.0 PTF-6 and higherProblem descriptionA table load fails with the message 'Missing management subscription for subscription XXX'Problem summaryIf 'continuous incremental updates' are enabled, the loading incrementally updated tables might fail.Problem conclusionThe problem has been fixed. An alternative workaround is to disable 'continuous incremental updates', load the tables, and re-enable the feature.
- Slow load performance on growth-on-demand systems with limited resourcesAffected usersAll users of IBM DB2 Analytics Accelerator for z/OS Version 5.1.0Problem descriptionLoad jobs do not perform as fast as on systems without resource limitsProblem summaryThe problem occurs if system resources were limited by the option 'Set a system-wide resource limit' on the IBM DB2 Analytics Accelerator Console.Problem conclusionThe problem has been fixed.
- Current timestamp discrepancy between DB2 and Accelerator (APAR PI85560)Affected usersAll users of IBM DB2 Analytics Accelerator for z/OS Version 5.1.0Problem descriptionIf a query which uses the special register "current timestamp" is being offloaded to the accelerator, the timestamp returned might be different from DB2 when the DB2 local timezone has an offset to the UTC timezone (e.g. UTC-7). The offset is being calculated into the opposite direction.Problem conclusionThe problem has been fixed with PTF UI49630.
- Multi-Row inserts into Accelerator-Only tables fail with SQL0904N (APAR PI85615)Affected usersAll users of IBM DB2 Analytics Accelerator for z/OS Version 5.1.0Problem descriptionIf a column contains a new line character, chr(10) or chr(13), the insert statement fails with the following error: <TASK_..-WRITER_1_*_> SEVERE: WRT_8229 Database errors occurred: IBM CLI Driver DB2 SQL0904N Unsuccessful execution caused by an unavailable resource. Reason code: " External Table : count of bad input rows reached maxerrors limit", type of resource: "", and resource name: "". SQLSTATE=57011 {Row=1} sqlstate = 57011 Database driver error...Problem conclusionThe problem has been fixed with PTF UI49630.
Migration recommendations and considerations
For recommendations and considerations concerning migration to IBM DB2 Analytics Accelerator for z/OS Version 5.1.0 read here.
Known issues
- IBM Netezza AnalyticsFor known issues with the IBM Netezza Analytics stored procedure package in IBM DB2 Analytics Accelerator for z/OS Version 5.1.0, see:Encryption of Data in MotionFor 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:Transfer of software update packages from IBM DB2 Analytics Accelerator Studio not possibleSummaryIBM 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 workaroundThe 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:
- Use US English as the locale for IBM DB2 Analytics Accelerator Studio.
- 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
- Save and close the file. Then start the application.
If the system utilization is very high, the accelerator might restart automatically to recover from the overload situationSummaryThe 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 partitionsSolution or workaround- Check the system utilization.
- Adjust the system utilization as needed.
- Retry failed operations and continue.
The execution of an INSERT INTO ... SELECT ... FROM statement in an in-database transformation job might failSummaryIn 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 workaroundThis is an indication that the system limits were reached. Check the system utilization and adjust it to the capacity of the system.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 messagesSummaryIf 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 workaroundThis is an indication that the system limits were reached. Check the system utilization and adjust it to the capacity of the system.Insertion of integer and decimal values causes failure of IDT jobsSummaryThe 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 workaroundUse 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)
Tables cannot be added if their names contain special characters, such as tabs and newlinesSummaryTables cannot be added if their names contain special characters, such as tabs and newline characters.Solution or workaroundFix will be delivered in a later release.Large number of accelerator-shadow tables might extend time needed to activate incremental updatesSummaryIf 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 workaroundReduce the number of tables that are activated in a single batch job to less than ten (<10).If the system utilization is high, load operations might fail with a message "Failed to start child transaction in session " -LocksharedObjectWait: LockAcquire failed".SummaryUnder a high system load, load operations might fail with a message "Failed to start child transaction in session " -LocksharedObjectWait: LockAcquire failed".Solution or workaroundRetry the load operation.ALTER TABLE ALTER PARTITION is not blocked by a partition in PRO State (DB2 V11 only)SummaryA 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 workaroundBecause a read-only partition was changed, a following restore operation will probably fail. The problem has been fixed in DB2 V12.
How to identify tables which should be reloaded after an installation of V5.1.0 maintenance level PTF-5 (only if maintenance level is "V5.1.0 GA" or "V5.1.0 PTF-1", without hot fix UI37271)
STEP 1: Identify the tables which could be affected- 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.
STEP 2: For all identified tables, disable query acceleration. For more information, see Disabling query acceleration for tables
STEP 3: Install V5.1.0 PTF-5.
STEP 4: Automatic conversion- Immediately after the upgrade to V5.1.0 PTF-5, 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.
STEP 5: Reloading tablesWithin the first hour after installation of the new accelerator server code, you might see a "DSNX881I -W 2004 ... Not all zone map records are consistent with the expected layout." message in the SYSLOG, which reports conversion failures. This is normal if the amount of data to be converted is high. The conversion failures are caused by a timeout mechanism. Check the SYSLOG one hour after the installation of the accelerator server. If you see zero or at most one DSNX88I-2004 message, the conversion has finished successfully and you can start with the full-table reload of the identified tables. If you see more than one DSNX88I-2004 message, check the SYSLOG again after 7 hours. If further messages show up, you might have a real conversion problem. In this case, contact IBM support. STEP 6: Enable query acceleration after a full table reload. For more information, see Enabling tables for query accelerationClick on the image to enlarge it[{"Product":{"code":"SS4LQ8","label":"Db2 Analytics Accelerator for z\/OS"},"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Component":"Not Applicable","Platform":[{"code":"PF035","label":"z\/OS"}],"Version":"5.1.0","Edition":"","Line of Business":{"code":"LOB10","label":"Data and AI"}}]
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Document Information
Modified date:
08 August 2018
UID
swg27050024