我可以在INSERT语句中使用子查询吗? [英] Can I use a subquery inside an INSERT statement?

问题描述

我需要在表中插入一行，其中一个字段值是从另一张表中计算出来的.我认为最好只用一条语句完成所有操作，而不是进行两个查询并冒一个竞赛条件的风险.

I need to insert a row into a table, with one field value being calculated from another table. Rather than doing two queries and risking a race condition, I thought it'd be better to do it all in one statement.

INSERT INTO `myTable` (`someData`, `averageAtThisTime`)
VALUES (
    "some stuff",
    SELECT AVG(`myField`) FROM `myOtherTable`
)

...但这不起作用.有没有一种方法可以在一个语句中实现呢?如果没有，您有什么建议?

... but this doesn't work. Is there a way I can achieve this in one statement? If not, what's your recommendation?

推荐答案

INSERT INTO `myTable` (`someData`, `averageAtThisTime`)
select "some stuff", AVG(`myField`) 
FROM `myOtherTable`

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