top button
Flag Notify
    Connect to us
      Site Registration

Site Registration

What is CDC in Informatica and what is the purpose of using it? Explain with an example?

+3 votes
483 views

What is CDC in Informatica, What is the purpose of using it? Please explain with an example?

posted Jan 11, 2016 by Sachin

Share this question
Facebook Share Button Twitter Share Button LinkedIn Share Button

1 Answer

0 votes

Hope everyone knows SCD Type-2. In that,

Insert Record if it is coming for first time.
Update Record the record it is already exists in Target.

Here the CDC comes into picture. Based on the primary key, we will check whether the record is present or not in the target. If it is, then update. So why don't we have a scenario, if that the record is coming without any changes in the data. Then also we are simply updating the data with again the same data that the table is having.

So to avoid this unncecessary updates which is not required. We will capture the changed records only. That is called Change Data Capture.

How to Implement ?

Now, we will maintain one more column in the target to. So while loading the data into the target, we have to calculate this. So MD5 Informatica Function will do this. For more on MD5, refer help.

MD5 will give the checksum value, 32 digit hexa-decimal unique value it will generate.

MD5(col1||col2||col3) -- This value we will insert into the target, if the record is coming for first time also. When the record is coming for next time. We will check the MD5 value of incoming record with the MD5 value of the target. So if there is no change then there is not change in the data. If it doesn't matches, then there is some changes happened in the record.

So like this, instead of blindly updating the record even though there are no changes happened for the record. CDC will do it in an efficient way. If you don't use CDC also nothing will happen, the results will not effect. But unnecessarily, you are reading and writing the same records which effects the performance.

answer Jan 11, 2016 by Manikandan J
Similar Questions
+5 votes

I gone through the RFC4006 but didnt get the context of below paragraph

   Certain applications require multiple credit-control sub-sessions.
   These applications would send messages with a constant Session-Id
   AVP, but with a different CC-Sub-Session-Id AVP.  If several credit
   sub-sessions will be used, all sub-sessions MUST be closed separately
   before the main session is closed so that units per sub-session may
   be reported.  The absence of this AVP implies that no sub-sessions
   are in use.

But here my question is
1. What could be the types of Multiple credit-ontrol Sub-session?
2. How can we include different cc-sub-session-ID for each sub-session, please give me an example with message structure using CCR message.

...