Change Data Delivery

abhijeet266das · Post by **abhijeet266das** » Fri Jan 04, 2013 8:23 am

Hi

Can you please let me know how does a Change Data Delivery Product work with Datastage.We need to provide an estimates to the customer.I only know this is a product of IBM infosphere

Thanks
Abhijeet

ray.wurlod · Post by **ray.wurlod** » Fri Jan 04, 2013 2:26 pm

There are a number of ways in which it can work. Typically changes to the database are captured by reading the transaction log (though triggers can also be used); these changes are placed onto an MQ series queue and a Change Data stage in DataStage can read from that queue.

I have no idea what kind of estimates your customer requires.

chulett · Post by **chulett** » Sat Jan 05, 2013 9:12 am

... or how you can provide estimates for something you have no experience with or knowledge of.

abhijeet266das · Post by **abhijeet266das** » Mon Jan 07, 2013 12:53 am

Thanks Ray.I am not a premium member so not able to view the content.
@Craig..Yeah i understand but i have been forced to do a poc on the same within a week and come up with the estimates after that for which i need to understand how it works.

chulett · Post by **chulett** » Mon Jan 07, 2013 7:40 am

Official information is here on the off chance you haven't seen it yet. The link is for Change Data Capture and there is another link to the Change Data Delivery product near the bottom.

Why not engage IBM or other consultancy that specializes in things like Proof of Concepts and is familiar with the product? All forcing someone like you to do this will result in (and this is no knock on you) is failure, I'm afraid.

BI-RMA · Post by **BI-RMA** » Mon Jan 07, 2013 7:47 am

Now, just to understand this a bit better. Your customer asked you to prepare a proof of concept for a technology you haven't got a clue about - within one week.

So you are going to present an estimate about some whatsoever after this week. What exactly is this going to prove concerning the overall concept?

Let me quote one of Ray's favourites: "Resist stupid requirements."

rsripathy · Post by **rsripathy** » Mon Jan 07, 2013 3:52 pm

ray.wurlod wrote:There are a number of ways in which it can work. Typically changes to the database are captured by reading the transaction log (though triggers can also be used); these changes are placed onto an MQ ...

Is there difference between,,, Change Data Delivery & Change Data Capture ? If so what ?

chulett · Post by **chulett** » Tue Jan 08, 2013 7:49 am

rsripathy wrote:Is there difference between,,, Change Data Delivery & Change Data Capture ? If so what ?

See the link in my previous post.

vmcburney · Post by **vmcburney** » Tue Jan 08, 2013 6:42 pm

What do you mean when you say "provide an estimate to the customer" - do you mean the cost of buying, installing or implementing? For buying Change Data Capture is priced on the size of each source and target database using a PVU calculation. Change Data Detection is the same technology but is priced on the size of the DataStage server that data is replicated to with unlimited source databases. As a rule of thumb CDC is the better license for up to three source systems and CDD becomes cheaper when replicating more than 3 databases.

For installing CDD is technically easy to install and politically a minefield. It can take a week to install but it can take six months to convince a team of DBAs that it should be installed and will not cause harm, and your DBAs need to know how to optimize database logging.

In terms of implementing it provides data integration at a fraction of the cost of ETL for data synchronisation when used correctly. If you want to stage data from a source system you can configure and bring multiple tables in just an hour or two. CDD requires a solution architect so you work out how it should be used and how it fits in to Warehouse layers.

abhijeet266das · Post by **abhijeet266das** » Wed Mar 06, 2013 4:44 am

Thanks a lot gentlemen for the assistance on the same.I got the product installed and carried out a poc on the same.i am confident now.Sorry for the delayed response.