如何在postgresql中获取唯一约束的名称？

I need to drop a unique constraint from a postgresql table, but I didn't give it a name in the schema. Does anybody know, how to get the name of such a constraint, or how to drop it?

我需要从postgresql表中删除一个唯一约束，但我没有在模式中给它一个名字。有谁知道，如何获得这种约束的名称，或者如何删除它？

2 个解决方案

#1

That is something like (for single column constaint):

这就像（对于单列constaint）：

tableName_columnName_key

To get constaint name write (in psql):

要获得constaint name write（在psql中）：

\d tableName

or use pg_constraint system catalog:

或使用pg_constraint系统目录：

SELECT conname
FROM pg_constraint
WHERE conrelid =
    (SELECT oid 
    FROM pg_class
    WHERE relname LIKE 'tableName');

Also you can get it from pgAdmin in objects tree.

您也可以从对象树中的pgAdmin获取它。

#2

SELECT conname
FROM pg_constraint
WHERE conrelid = 'mytable'::regclass::oid

#1