How to enable table relationship diagram in sql server 2008 management studio ?
You should not have to do anything special. Simply select the database diagrams under the database you are interested in. If they do not already exist, you may get a message that some support objects are needed, but all you need to do is give SSMS permission to create them and it will do it automtically.
Are you getting some specific error or having some specific problem trying to access the database diagrams?
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