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假设我有一张名为CAT
CAT
CAT有两列ID和NAME
ID
NAME
我忘了为这两列添加唯一约束。在我的数据库中，我想确保在添加该约束之前没有任何错误的条目。
所以我想要一个查询来确保每个列ID中都有唯一的值NAME。我该如何查询这个？