如何为 MySQL 中的多个列指定唯一约束？

Question

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?

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

转载于:https://stackoverflow.com/questions/635937/how-do-i-specify-unique-constraint-for-multiple-columns-in-mysql

Answer 1

ALTER TABLE `votes` ADD UNIQUE `unique_index`(`user`, `email`, `address`);