How Can I Create a Unique Constraint on My Column (Sql Server 2008 R2)?
I Have Sql Server 2008 R2 and I Want to Set a Unique Column. There Seems to Be Two Ways to Do This: "Unique Index" and "Unique Constraint". They Are Not Much...
I have SQL Server 2008 R2 and I want to set a unique column.
There seems to be two ways to do this: "unique index" and "unique constraint". They are not much different from what I understand, although unique constraint is recommended by most, because you also get an index automatically.
How do I create a unique constraint?
ALTER TABLE Customer ADD CONSTRAINT U_Name UNIQUE(Name)
Is there a way to create a unique constraint through the SQL Server Management Studio?
5 Answers
Set column as unique in SQL Server from the GUI:
They really make you run around the barn to do it with the GUI:
Make sure your column does not violate the unique constraint before you begin.
- Open SQL Server Management Studio.
- Right click your Table, click "Design".
- Right click the column you want to edit, a popup menu appears, click Indexes/Keys.
- Click the "Add" Button.
- Expand the "General" tab.
- Make sure you have the column you want to make unique selected in the "columns" box.
- Change the "Type" box to "Unique Key".
- Click "Close".
- You see a little asterisk in the file window, this means changes are not yet saved.
- Press Save or hit Ctrl+s. It should save, and your column should be unique.
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