Tuesday, September 9, 2008

Change data capture

Identifying and extracting changed data from source tables was replete with lots of efforts; it also requires designing the databases in an appropriate manner for keeping the changed data within tables or log files. The concept of “Change data capture”, a set of software design patterns used to determine (and track) the data that has changed in a database, helps designers to overcome the difficulty of solving such problems.

Fortunately, SQL Server 2008 implemented a mechanism to enable DBAs for automating this process like what we could consider in Oracle 9i which is called “Capturing Change”.
By using this new feature we could specify a log table in which the changes in data could be tracked. These changes are insert, update, and delete. SQL Server 2008 handles the required operation to store the appropriate data.

The following links are very helpful for understanding this new feature which could make ETL process more easily.

http://en.wikipedia.org/wiki/Change_data_capture
http://msdn.microsoft.com/en-us/library/cc645937(printer).aspx
http://www.oracle.com/technology/oramag/oracle/03-nov/o63tech_bi.html

8 comments:

Pedro said...

Very good post my friend!!!
The CDC only works if the source is a Database SQL Server, correct?

When you go to uk to take the master!?

Regards!!!
Pedro

Amin said...

Hi Pedro,

Indeed, CDC is a feature that recently supplied with microsoft for SQL Server 2008. Still, Oracle implemented it some years ago, and it is not limited to SQL Server.
Universities Addmission will be open at Dec 1st, so if I will be accepted I will be in Europ next year ;)

Best wishes,
Amin

Anonymous said...

Hi Amin,

How are you? I see I haven't visited here for far too long and I really regret it!
The news of your blog's anniversary and your upcoming studies didn't reach me till now, though I'm very happy to hear about both. Are you aiming at studying in a specific country? Are you planning on taking courses in technological studies or something more financial?
In any case, I'm sure you'll have a lot more to contribute to us so keep up the good blog and thank you for sharing!

All the best,
Ella

Amin said...

Hi Ella,

I am fine, thank you.
I am very happy to see your comment here. Indeed, I am going to study in Nordic countries. I like to study Information Systems which focuses on business intelligence. However, I will apply for some technical programs which are my second preference.

Unfortunately, I could not apply for United Kingdom’s universities because they are very expensive.

I wish I will be accepted, and I also wish to see all of you.

Best wishes,
Amin

Anonymous said...

Hi Amin,

I wish you then the best of luck. Keep us posted!

Regards,
Ella

Anonymous said...

Nice blog.
Excellent content.

Bravo.

Please visit:

http://global-homebiz.blogspot.com

Good luck

Pedro said...

Hi amin!
If I can help you in anything tell me!!!
Cheers!!
pedro

Amin said...

Hi Pedro,

Thank you very much, It is your kindness.
Time is the only think that I am seeking ;)

Cheers my friend,
Amin