SQL Server Performance Forum – Threads Archive

SCDs and AS 2000

Hello,
I am totally frustrated in trying to understand SCDs in a practical setting. What is odd, is that there is little on the web that actually explains the issues with altering cubes regarding SCDs.
Heres a burning issue for me : If I have an existing cube built in SQL 2000 AS which is processed fully after having its dimensions and fact tables updated each night. I have a dimension that some idiot keeps altering values in and when we process the cube, the cube crashes out with a dimension processing error. We have datamarts that we draw our cube data and dimension data from. I am pretty sure its because changes have been made to the dimensions in the datamarts that supply the cube which is causing the issue. Can I get around this issue by altering the currently troublesome shared dimension to become a changing dimension, by changing the "changing" property from "False" to "True", or have I missed something? This is driving me crazy, as there seems to be a gap in info between advanced cube knowledge and very basic cube knowledge. Any help most welcome – an answer will be truly a valued resource on the web….. Thank you in advance…… Steve.

Yes you can make a dimension to behave as SCD by going to dimension editor and in advanced property make changing property from false to true.
The only impact will be on mdx query performance but you will gain on cube processing.
Depending on the cube designed, where query performance is of little issue, you can change the dimension to SCD and also if you are less bothered about storing history

also check this link for concept of SCD:
http://www.1keydata.com/datawarehousing/scd-type-1.html

You may try to buy Kimball’s toolkit book that is sql server dedicated. I haven’t read it, but I think it might be a good idea.

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