CDC Implementation

Document ID : KB000122195
Last Modified Date : 10/12/2018
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Question:
We are considering implementing CDC and have some general questions.
1) Can all applications tables be monitored by CDC?
2) What is the approximate added overhead?
3) What is CDC Plus and what does it buy?
4) Can the monitor be on the mainframe and the listener by on another platform? l
Environment:
z/os, CA Datacom/DB 15.1
Answer:
I have replicated your questions and then provided a responses with a "==>" prefix. 

We are considering implementing CDC and have some general questions. 

1) Can all applications tables be monitored by CDC? 

==> Yes, as long as the tables are LOG=YES, RECOVERY=YES 


2) What is the approximate added overhead? 

==> Overhead variable and is based on how much maintenance activity is being captured. 

For most shops maintenance activity is a small percentage of request (10-15%) 

Overhead can be shifted from the PROD MUF for CDC activity to a special CDC replication MUF 

The CDC replication MUF does not reduce the overhead, but moves it out of the PROD MUF to a separate address space 


3) What is CDC Plus and what does it buy? 

==> CDC plus allows the user to separate the captured changes to different (max 9) CDC repository databases 

The separate repository databases allows the customer to separate captured changes by monitored table name so that we can isolate changes in the target repository database according to application function or security requirements. 


4) Can the mainframe send CDC to another platform? 

==> CDC itself does not "send" data to other platforms -- it just captures the changes and stores them is a standard database table to be processed 

==> CA provides a listener/applier process specific to Datacom MUF (zOS) to Datacom MUF (zOS) movement (replication) thru MQ. This is part of an Active/Query implementation. 

==> There are 3rd parties (like Power Exchange, GT Software) that have tools that read the Datacom CDC database and forward the changes to off platform processes. 
Additional Information:
See Change Data Capture (CDC) documentation and CDC Plus datavases:
http://docops.ca.com/ca-datacom/15-1/en/administrating/ca-datacom-db-database-and-system-administration/using-the-multi-user-facility/change-data-capture

http://docops.ca.com/ca-datacom/15-1/en/administrating/how-to-build-the-cdc-plus-databases