SQL Clone
SQLServerCentral is supported by Redgate
 
Log in  ::  Register  ::  Not logged in
 
 
 


Slowly Changing Dimensions


Slowly Changing Dimensions

Author
Message
agrawal.prakriti
agrawal.prakriti
Old Hand
Old Hand (342 reputation)Old Hand (342 reputation)Old Hand (342 reputation)Old Hand (342 reputation)Old Hand (342 reputation)Old Hand (342 reputation)Old Hand (342 reputation)Old Hand (342 reputation)

Group: General Forum Members
Points: 342 Visits: 101
Comments posted to this topic are about the item Slowly Changing Dimensions
Stewart "Arturius" Campbell
Stewart "Arturius" Campbell
SSC-Dedicated
SSC-Dedicated (35K reputation)SSC-Dedicated (35K reputation)SSC-Dedicated (35K reputation)SSC-Dedicated (35K reputation)SSC-Dedicated (35K reputation)SSC-Dedicated (35K reputation)SSC-Dedicated (35K reputation)SSC-Dedicated (35K reputation)

Group: General Forum Members
Points: 35671 Visits: 7706
Good question

____________________________________________
Space, the final frontier? not any more...
All limits henceforth are self-imposed.
“libera tute vulgaris ex”
Arjun SreeVastsva
Arjun SreeVastsva
SSCarpal Tunnel
SSCarpal Tunnel (4.7K reputation)SSCarpal Tunnel (4.7K reputation)SSCarpal Tunnel (4.7K reputation)SSCarpal Tunnel (4.7K reputation)SSCarpal Tunnel (4.7K reputation)SSCarpal Tunnel (4.7K reputation)SSCarpal Tunnel (4.7K reputation)SSCarpal Tunnel (4.7K reputation)

Group: General Forum Members
Points: 4650 Visits: 1711
Type 1 Slowly Changing Dimension data warehouse architecture applies when no history is kept in the database. The new, changed data simply overwrites old entries. This approach is used quite often with data which change over the time and it is caused by correcting data quality errors (misspells, data consolidations, trimming spaces, language specific characters).
Type 1 SCD is easy to maintain and used mainly when losing the ability to track the old history is not an issue.
Arjun SreeVastsva
Arjun SreeVastsva
SSCarpal Tunnel
SSCarpal Tunnel (4.7K reputation)SSCarpal Tunnel (4.7K reputation)SSCarpal Tunnel (4.7K reputation)SSCarpal Tunnel (4.7K reputation)SSCarpal Tunnel (4.7K reputation)SSCarpal Tunnel (4.7K reputation)SSCarpal Tunnel (4.7K reputation)SSCarpal Tunnel (4.7K reputation)

Group: General Forum Members
Points: 4650 Visits: 1711
Slowly changing dimension Type 2 is a model where the whole history is stored in the database. An additional dimension record is created and the segmenting between the old record values and the new (current) value is easy to extract and the history is clear.
The fields 'effective date' and 'current indicator' are very often used in that dimension and the fact table usually stores dimension key and version number.
SQLRNNR
SQLRNNR
SSC Guru
SSC Guru (145K reputation)SSC Guru (145K reputation)SSC Guru (145K reputation)SSC Guru (145K reputation)SSC Guru (145K reputation)SSC Guru (145K reputation)SSC Guru (145K reputation)SSC Guru (145K reputation)

Group: General Forum Members
Points: 145717 Visits: 18652
Nice question. Thanks

Jason...AKA CirqueDeSQLeil
_______________________________________________
I have given a name to my pain...MCM SQL Server, MVP
SQL RNNR
Posting Performance Based Questions - Gail Shaw
Learn Extended Events

Paul White
Paul White
SSC Guru
SSC Guru (80K reputation)SSC Guru (80K reputation)SSC Guru (80K reputation)SSC Guru (80K reputation)SSC Guru (80K reputation)SSC Guru (80K reputation)SSC Guru (80K reputation)SSC Guru (80K reputation)

Group: General Forum Members
Points: 80530 Visits: 11400
I look forward to Raju The Leader (???) enlightening us all about Type 3 SCDs Laugh



Paul White
SQLPerformance.com
SQLblog.com
@SQL_Kiwi
Go


Permissions

You can't post new topics.
You can't post topic replies.
You can't post new polls.
You can't post replies to polls.
You can't edit your own topics.
You can't delete your own topics.
You can't edit other topics.
You can't delete other topics.
You can't edit your own posts.
You can't edit other posts.
You can't delete your own posts.
You can't delete other posts.
You can't post events.
You can't edit your own events.
You can't edit other events.
You can't delete your own events.
You can't delete other events.
You can't send private messages.
You can't send emails.
You can read topics.
You can't vote in polls.
You can't upload attachments.
You can download attachments.
You can't post HTML code.
You can't edit HTML code.
You can't post IFCode.
You can't post JavaScript.
You can post emoticons.
You can't post or upload images.

Select a forum








































































































































































SQLServerCentral


Search