How to change the DB2 Version from ESE to WSE

If you need to change DB2 version , you have to either a)uninstall the old version or b) upgrade it to the new version. In these notes, I am uninstalling the old version. In this example, I am changing DB2 versions from DB2 10.1 ESE to DB2 10.1 WSE Step 1: Contact application owners to shutdown application connections to the DB2 instances stopped. You can check for any live connections with: db2 list applications Step 2: Backup, export or db2move. This decision depends on the circumstances # mkdir /backups # cd /backups # db2look -d DBNAME -e -o DBNAME.DDL #... Read more →

ADM7519W DB2 could not allocate an agent. The SQLCODE is "-1225".

Question: We’re running an application which connects to a DB2 9.7 on Red Hat Linux 6. On the last batch job the following error message was reported. --application side Connection reset. ERRORCODE=-4499, SQLSTATE=08001 -- The associated messages in the db2diag.log were ADM7009E An error was encountered in the "TCPIP" protocol support. A possible cause is that the maximum number of agents has been exceeded. ADM7519W DB2 could not allocate an agent. The SQLCODE is "-1225". Answer: Some background information. The configuration parameter MAXAGENTS is set at the instance level , therefore an aggregate of all active databases. Each database has... Read more →

Database Tuning for complex sql queries

Question: I manage a large DB2 data warehouse. The datawarehouse supports multiple ETL processes . Sometimes , some SQL queries fail. The large SQL queries are attempting to extract a large amount of data and are complex. What DB2 parameters can I consider changing to fix this problem? Answer: Firstly , ensure the indexes are maintained correctly. Are statistics up to date? Are fragmentation levels low? Are REORG on tables running regularly? For large complex queries , I normally look at the SQL statement heap (STMTHEAP) , default application heap (APPLHEAPSZ), and the package cache size (PCKCACHESZ) The DB2 STMTHEAP... Read more →

Running a Java Program from Command Prompt

Question: I’m receiving this message when attempting to compile some java code: 'javac' is not recognized as an internal or external command, operable program or batch file How can I fix this problem? Answer: If you installed the JDK in C:\jdk1.6.0. At the prompt you would type the following command and press Enter: C:\jdk1.6.0\bin\javac MyDB2.java If you choose this option, you'll have to precede your javac and java commands with C:\jdk1.6.0\bin\ each time you compile or run a program. If the system cannot find javac or java, check the set path command. It is possible to make the path setting... Read more →

DB2 LOGINDEXBUILD

According to the DB2 documentation, the LOGINDEXBUILD database configuration parameter “specifies whether index creation, recreation, or reorganization operations are to be logged so that indexes can be7 reconstructed during DB2 rollforward operations or high availability disaster recovery (HADR) log replay procedures” db2 get db cfg for mydb | grep 'LOGINDEXBUILD' Log pages during index build (LOGINDEXBUILD) = OFF| ON Notes 1) For HADR the recommendation is to have LOGINDEXBUILD turned on. This will create extra log files . Need to complete a capacity planning task. Capacity planning for log space required during an index build can be complicated – as... Read more →