mysql 使用另一个表中的值更新列

2021-11-20 00:00:00 sql-update sql mysql

我有两张桌子，看起来都像

I have two tables, both looking like

id  name  value
===================
1   Joe     22
2   Derk    30

我需要根据每个表中的检查名称将value的值从tableA复制到tableB.

I need to copy the value of value from tableA to tableB based on check name in each table.

对于这个 UPDATE 语句有什么提示吗?

Any tips for this UPDATE statement?

推荐答案

除了这个答案，如果您需要根据 tableA.value 动态更改 tableB.value，您可以这样做，例如:

In addition to this answer if you need to change tableB.value according to tableA.value dynamically you can do for example:

UPDATE tableB
INNER JOIN tableA ON tableB.name = tableA.name
SET tableB.value = IF(tableA.value > 0, tableA.value, tableB.value)
WHERE tableA.name = 'Joe'

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