sql,SELECT column_name, COUNT(*),FROM table_name,GROUP BY column_name,HAVING COUNT(*) > 1;,
``,,这段代码会返回所有在指定表中重复出现的字段及其出现次数。sql,SELECT column_name, COUNT(*),FROM table_name,GROUP BY column_name,HAVING COUNT(*) > 1;,
``,,这段代码会返回所有在指定表中重复出现的字段及其出现次数。GROUP BY
子句和 HAVING
子句。假设你有一个名为 users
的表,并且你想查找重复的 email
字段,你可以使用以下查询:,,``sql,SELECT email, COUNT(*),FROM users,GROUP BY email,HAVING COUNT(*) > 1;,
`,,这个查询会返回所有在
users 表中出现次数超过一次的
email` 及其出现的次数。Powered By Z-BlogPHP 1.7.3
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