DB2 对多列的唯一约束 [英] DB2 Unique Constraint over multiple Columns

问题描述

有没有办法像在 Mysql 中一样在多个列上创建唯一约束?

Is there a way to create a unique constraint over multiple columns like in Mysql?

UNIQUE KEY `uniqueKey` (`Field1`,`Field2`),

我唯一找到的是字段后面的唯一关键字.

The only thing i have found is the unique keyword directly after the field.

提前致谢！

推荐答案

你应该能够添加一个唯一的约束为:

You should be able to add a unique constraint as:

ALTER TABLE t ADD CONSTRAINT unq_field1_field2 UNIQUE(field1, field2)

与其他数据库一样，这几乎完全等同于创建索引.不同的是，给约束命名——这样可以方便跟踪约束和理解错误信息.

As with other databases, this is almost exactly equivalent to creating an index. The difference is that the constraint is named -- which can be convenient for tracking constraints and understanding error messages.

注意，如果匹配索引不存在，那么唯一索引是 自动创建.

Notice, that if the matching index does not exist, then a unique index is automatically created.

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