我有
Update2 `Table1` AS T1 Inner Join `Table2` As T2
On T2.`Name` = T1.Name
Set T1.`ParentID` = T2.`ID`
我想先检查一下,长周末后大脑卡住,感谢帮助。
我基本上想先检查一下
Select FieldA, concat(FieldC,', ',FieldD) `Table1` AS T1 Inner Join `Table2` As T2
on T2.`Name` = T1.Name
Set T1.`ParentID` = T2.`ID`
确保我得到正确的结果。
最佳答案
等效的 SELECT 可以是:
SELECT T1.`ParentID` = T2.`ID`
FROM `Table1` AS T1 Inner Join `Table2` AS T2
ON T2.`Name` = T1.Name
pt-query-digest是将 UPDATE 转换为 SELECT 以便运行 EXPLAIN 的工具示例。
关于mysql - 将更新/加入变成查询,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/19483108/