Blobs block online indexing - SimonS Blog on SQL Server Stuff

Blobs block online indexing

If you are lucky enough to be running enterprise edition of SQL you may have looked or want to look into online index rebuilds. Unfortunately having blobs in your index blocks you from being able to do online rebuild of that index. Cruically what that means is that if your table is clustered then you cannot rebuild the clustered index on that table

You can still reorganise you index with blobs.

For this reason my reccomendation is to consider seperating out your blob data into another table. For instance if you stored articles in your database, you would have an article table. In this table you will store the contents of the article along with other information about the article. Many queries are likely to query the information and not the article contents. If you stored the article contents on the same table as the other information you wouldn't be able to re-index the table if it had a clustered index.

So in this scenario you would be best off with an Article and ArticleContents table.

This mechansim is also of benefit if using a full text index. Having a seperate table allows you to isolate full text to that table. In addition it allows you to drop, recreate and even repopulate your data without impacting your main table with the core information in it.



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Published 27 June 2007 09:33 by simonsabin

Comments

06 July 2007 14:41 by Jason Haley

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