问题描述
类似于这个问题,但对于 MySQL....p>
如何以编程方式确定 MySQL 中的外键引用(假设为 InnoDB)?我几乎可以得到它们:
显示表状态其中名称 = 'MyTableName';
...但是很可惜,似乎包含其中一些信息的评论栏被截断了,所以我不能依赖它.一定有别的办法……
我对 C API 调用、SQL 语句以及任何东西都很满意——我只需要一些始终有效的东西.
注意:我也考虑过解析SHOW CREATE TABLE MyTableName"语句的结果,但我真的希望有更简单的方法.
您可以查询两个表来获取此信息:INFORMATION_SCHEMA.TABLE_CONSTRAINTS
和 INFORMATION_SCHEMA.KEY_COLUMN_USAGE
.
这是来自上面链接的后一页评论的查询,它演示了如何获取您寻求的信息.
SELECT CONCAT(table_name, '.', column_name, '->',referenced_table_name, '.', referenced_column_name ) AS list_of_fksFROM INFORMATION_SCHEMA.key_column_usageWHERE referenced_table_schema = '测试'AND referenced_table_name 不为空按表名、列名排序;
使用您的架构名称而不是上面的test
".
Similar to this question but for MySQL....
How can I programmatically determine foreign key references in MySQL (assuming InnoDB)? I can almost get them with:
SHOW TABLE STATUS WHERE Name = 'MyTableName';
...but alas, the comment column which seems to contain some of this info gets truncated so I can't rely on it. There must be some other way...
I'd be happy with a C API call, a SQL statement, anything--I just need something that consistently works.
Note: I've also considered parsing the results of a "SHOW CREATE TABLE MyTableName" statement, but I'm really hoping there's something simpler.
There are two tables you can query to get this information: INFORMATION_SCHEMA.TABLE_CONSTRAINTS
and INFORMATION_SCHEMA.KEY_COLUMN_USAGE
.
Here's a query from the comments on the latter page linked above, which demonstrates how to get the info you seek.
SELECT CONCAT( table_name, '.', column_name, ' -> ',
referenced_table_name, '.', referenced_column_name ) AS list_of_fks
FROM INFORMATION_SCHEMA.key_column_usage
WHERE referenced_table_schema = 'test'
AND referenced_table_name IS NOT NULL
ORDER BY table_name, column_name;
Use your schema name instead of 'test
' above.
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