Enabling Change Capture

Configure DB2 to log data changes in the expanded format that is supplied by the DATA CAPTURE CHANGES feature of the CREATE TABLE and ALTER TABLE commands. This format provides Oracle GoldenGate with the entire before and after images of rows that are changed by update statements. You can use GGSCI to issue the ALTER TABLE command as follows.

To Enable Change Capture from GGSCI:

From the Oracle GoldenGate directory, run GGSCI.
Log on to DB2 from GGSCI as a user that has ALTER TABLE privileges. Specify the data source name with SOURCEDB and specify the user login with USERID and PASSWORD.
```
DBLOGIN SOURCEDB dsn, USERID user[, PASSWORD password] 
```
Issue the following command. where owner.table is the fully qualified name of the table. You can use a wildcard to specify multiple table names. Only the asterisk (*) wildcard is supported for DB2 LUW.
```
ADD TRANDATA owner.table
```
ADD TRANDATA issues the following command, which includes logging the before image of LONGVAR columns:
```
ALTER TABLE name DATA CAPTURE CHANGES INCLUDE LONGVAR COLUMNS; 
```

Example 4-1 To Exclude LONGVAR Logging:

To omit the INCLUDE LONGVAR COLUMNS clause from the ALTER TABLE command, use ADD TRANDATA with the EXCLUDELONG option.

ADD TRANDATA owner.table, EXCLUDELONG

Note:

If LONGVAR columns are excluded from logging, the Oracle GoldenGate features that require before images, such as the GETUPDATEBEFORES, NOCOMPRESSUPDATES, and NOCOMPRESSDELETES parameters, might return errors if tables contain those columns. For a workaround, see the REQUIRELONGDATACAPTURECHANGES | NOREQUIRELONGDATACAPTURECHANGES options of the TRANLOGOPTIONS parameter.