Maintaining and Monitoring Your Database : Change Data Capture : Enabling CDC
Enabling CDC
Before you can use CDC, you must enable it, and before you enable it, you should allocate space for the associated tables and indexes. The _Cdc-Change-Tracking table is the repository of all change capture data in a database. Once Change Data Capture is running, _Cdc-Change-Tracking can grow very quickly and become very large. It is important that you allocate enough space for this table and its indexes.
To allocate space for CDC in your database, add new areas with PROSTRCT ADD. You can use a structure file similar to the following:
#
# add_cdc.st
#
d "CDC_Track_Data":20,64;512 . f 102400
d "CDC_Track_Data":20,64;512 . f 102400
d "CDC_Track_Data":20,64;512 .
#
d "CDC_Track_Idx":21,1;64 . f 10240
d "CDC_Track_Idx":21,1;64 . f 10240
d "CDC_Track_Idx":21,1;64 .
#
And add it to your database, for example:
prostrct add db-needing-cdc add_cdc.st
After adding the areas for the CDC data and indexes, enable your database as follows:
proutil db-needing-cdc -C enablecdc
area CDC_Track_Data indexarea CDC_Track_Idx
In order to enable or disable the feature, the Table and Field Policies must be removed in a separate operation beforehand. Removing Table and Field policies causes all related Change Tables to be removed. Removing policies can be accomplished through OpenEdge Management or OpenEdge Explorer. The Policies and their related Change Tables can also be removed by a language table drop operation on the Source Table. The Feature Bit mechanism activated at enablement restricts direct connections to a CDC-enabled database from older releases.
