SQL Server Database Diagram – How to Create and Use

Although this question is a year old, if anyone stumble over this, I've posted a solution to make that possible here:

http://www.codeproject.com/Messages/4914888/Search-through-the-binary-for-all-contained-texts.aspx

The trick is to extract all ASCII characters in the diagram binary, you'll see that all table names are in there as simple text. That seems to be the reason why a diagram is also destroyed if you rename a table with a script - because it doesn't use a table ID to identify the table but the table name. If it's no longer there, the diagram is not usable anymore.

With this method you can identify which diagrams contains a specific table.

I would suggest NOT to use Designer in creating key constraints or doing any DDL / DML operations.

Best is to use T-SQL - much flexible, more options, more powerful and you can automate many things with it. There is a learning curve, but its worth learning TSQL rather than keep using GUI.

Also, make sure you are using the latest version of SSMS - sql server 2014. Download it from here.

Read up : Managing SQL Server via Management Studio vs TSQL Commands

e.g. From BOL

ALTER TABLE dbo.DocExc 
   ADD ColumnD int NULL 
   CONSTRAINT CHK_ColumnD_DocExc -----> This is your constraint
   CHECK (ColumnD > 10 AND ColumnD < 50);
GO