If you find yourself struggling with the following error message in SQL Server Management Studio 2005:
Database diagram support objects cannot be installed because this database does not have a valid owner. To continue, first use the Files page of the Database Properties dialog box or the ALTER AUTHORIZATION statement to set the database owner to a valid login, then add the database diagram support objects.
And you are sure that the database does in fact have a valid owner, check the "Compatibility Level" on the Options page. Make sure this is set to "SQL Server 2005."
alt="SQL Server 2005 compatibility level"/>
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Excellent Information.
Thanks! That saved me a lot of messing about.
Thanks for the info!
Any recommendations if a database still gives me the error after making this change? I have a couple other databases on the same instance that I performed this for and all issues were resolved, but for one I continue to run into the problem.
I guess I’m not enough of an expert to say when it comes to that.
I need compatibility set to SQL 2000. Is there another way?
If it still isn’t working for you there might be one more step that I need to perform when I restore a database from a different Sql Server 2000 Server: Change the database login to a different owner, and then if you want, back to the original to fix a discrepency that is created in the system tables with dbo. Make sure that the login that you are giving ownership to does not exist as a user in the database you are changing the owner for when you do.
This *might* be happening because the database I restored from the other server had diagrams in it already; I haven’t experimented to find the true cause yet. So if you find the time to figure out the particulars, please post - I’m curious.
Switch compatability to 90, click on digrams tab, install required objects, then set compatability to anything you like.
-j
I spent two hours yesterday… I’m disappointed I didn’t find this earlier. You have helped a lot!