MySQL：如果外键存在，则插入 [英] MySQL: Insert if foreign key exists

问题描述

问题是，我想插入2.000行的表格到我的数据库中。有一个引用另一个表中的外键的列。不幸的是，很多查询失败，因为提供的外键值不存在。

我知道我可以忽略外键检查，但这不是我想要的。我不想忽略外键检查，我只是希望执行不好的查询。

示例：

  INSERT INTO test（id，value）VALUES（10，20）; 
 INSERT INTO test（id，value）VALUES（20，20）; 
  

第一个查询失败，因为 TEST.id 引用 foobar.id 并且没有 foobar.id = 10。但是，第二个查询可以工作， foobar.id = 20 存在，但是第二个查询不会被执行，因为第一个查询已经失败。

有什么办法可以避免第一个查询出错，而其他查询仍然会被执行？

我可以编写一个php脚本，但是我更喜欢这里的一个MySQL解决方案。

插入select的结果，如下所示：

  INSERT INTO test（id，value）
 SELECT foobar。 id，20 
从foobar WHERE id = 10; 
  

I have an Excel sheet with around 2.000 rows that I want to insert into my database.

The problem is that the table I want to insert the 2.000 rows into has a column that references to a foreign key in another table. Unfortunately a lot of queries fail, since the provided foreign key value does NOT exist.

I know that I can ignore foreign key checks, but this is not what I want. I don't want to ignore foreign key checks, I just want bad queries not to be executed.

Example:

INSERT INTO test (id, value) VALUES (10, 20);  
INSERT INTO test (id, value) VALUES (20, 20);

The first query fails, since TEST.id references foobar.id and there is no foobar.id = 10. However, the second query would work, since foobar.id = 20 exists, but the second query won't be executed, because the first one already failed.

Is there any way I don't get an error on the first query and my other queries will still be executed?

I could write a php script, but I'd prefer a MySQL solution here.

解决方案

You could change to insert the result of a select, so something like:

INSERT INTO test (id, value) 
SELECT foobar.id, 20
FROM foobar WHERE id = 10;

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