How do I specify unique constraint for multiple columns in MySQL?

Posted by Niyaz on Stack Overflow See other posts from Stack Overflow or by Niyaz
Published on 2009-03-11T19:12:31Z Indexed on 2010/05/07 21:28 UTC
Read the original article Hit count: 235

Filed under:

mysql

|

constraints

|

table

|

database

|

query

I have a table:

table votes (
    id,
    user,
    email,
    address,
    primary key(id),
);

Now I want to make the columns user, email, address unique (together).

How do I do this in MySql?

Thanks in advance.

Of course the example is just... an example. So please don't worry about the semantics.

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