DB2 Version 9.7 for Linux, UNIX, and Windows

Migrating explain tables

If you must maintain explain table information that you previously gathered in your existing DB2® copies from previous releases, migrate your explain tables to DB2 Version 9.7.

You can manually migrate your explain tables after you upgrade your database, or you can later re-create the explain tables and gather new information.

If you plan to collect sections actuals, you must migrate your explain tables or re-create them in Version 9.7.

Before you begin

Ensure that you have DBADM authority. Additional authorization details are available in the Command Reference.

Procedure

To migrate the explain tables:

Run the db2exmig command:
```
db2exmig -d dbname -e explain_schema [-u userid password]
```
where:
- dbname represents the database name. This parameter is required.
- explain_schema represents the schema name of the explain tables to be migrated. This parameter is required.
- userid and password represent the current user's ID and password. These parameters are optional.
The explain tables belonging to the user ID that is running db2exmig, or that is used to connect to the database, are migrated. The explain tables migration tool renames the existing explain tables, creates a new set of tables using the EXPLAIN.DDL file, and copies the contents of the existing explain tables to the new tables. Finally, it drops the existing explain tables. The db2exmig command preserves any user added columns on the explain tables.
Use Visual Explain to see a graphical display of a query access plan or the db2expln command to see the access plan information in the migrated explain tables.