Find centralized, trusted content and collaborate around the technologies you use most.
Teams
Q&A for work
Connect and share knowledge within a single location that is structured and easy to search.
示例:在电话表上,有人有两个电话号码 SQL 会给我同一个人的第二行,但电话号码不同,而不是第二列。我使用什么查询来检查 person_id 是否多次出现在单独的列中插入第二行数据?
我希望这是有道理的。提前致谢!
尝试这样的事情:
SELECT person_id, COUNT(person_id) AS 'PersonIDCount' FROM phone_table GROUP BY person_id HAVING COUNT(person_id) > 1
该查询将返回多次插入相同 person_id 键的所有记录。