Chapter 5. Tools configuration and customization 119
5.1.4 Enable the EXPLAIN function
In Figure 5-9, notice Optimization Service Center or Optimization Expert allows you to create
the EXPLAIN tables:
1. Provide the desired information and click Next.
Figure 5-9 Connect - Enable EXPLAIN window
120 DB2 9 for z/OS: New Tools for Query Optimization
2. In Figure 5-10, the EXPLAIN table did not exist and Optimization Service Center or
Optimization Expert provides a confirmation window that allows you to create it.
Figure 5-10 Connect - Create EXPLAIN table
Chapter 5. Tools configuration and customization 121
3. You can override the CREATE options as seen in Figure 5-11. Click Next when you
complete the options.
Figure 5-11 Connect - Override EXPLAIN options window
122 DB2 9 for z/OS: New Tools for Query Optimization
4. Upon successful completion of the CREATE for the EXPLAIN tables, an information
message window displays, as shown in Figure 5-12. Click OK, then Next.
Figure 5-12 Connect - display successful CREATE of EXPLAIN tables
Chapter 5. Tools configuration and customization 123
5. An error occurs when the EXPLAIN tables are not in the same format as expected, as
shown in Figure 5-13. This happens in changes to code requiring a DROP of the old
EXPLAIN tables and a CREATE of the new tables. You can manually DROP the tables
displayed. Click OK and then Next.
Figure 5-13 Connect - EXPLAIN version mismatch window

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