问题描述
我有一个更新查询需要在 MySQL 中运行，但遇到了一些问题.我花了最后一个小时研究 SO 的解决方案，但找不到真正有效的解决方案.我需要执行以下操作:
I have an update query that I need to run in MySQL and am having some trouble with it. I have spent the last hour researching SO for a solution, but couldn't find one that actually worked. I need to do the following:
UPDATE TABLE1 SET ID = (SELECT TABLE2.ID FROM TABLE2, TABLE1
WHERE TABLE1.NAME=TABLE2.NAME) WHERE TABLE1.ID IS NULL
我收到了 错误代码:1242.子查询返回超过 1 行 错误.如何修改我的查询以使其成功运行?
I have been getting the Error Code: 1242. Subquery returns more than 1 row error. How can I modify my query to make it run successfully?
基本上，我需要根据条件从另一个表中填写一个列的所有值的空白.请在这个问题上指导我.谢谢！
Basically, I need to fill in the blanks of all values of one column based on a condition, from another table. Please guide me on this issue. Thank you!
推荐答案
UPDATE TABLE1, TABLE2
SET TABLE1.ID = TABLE2.ID
WHERE TABLE1.ID IS NULL
AND TABLE1.NAME = TABLE2.NAME
应该做你想做的，假设 NAME 对于所有名称在 TABLE1 和 TABLE2 中都是唯一的.
should probably do what you want, assuming that NAME is unique accross TABLE1 and TABLE2 for all names.
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