在数据库中如何查找表之间的连接

Question

I have a database and it has lot of tables. I want to find column names from tables that link them to each other. So as to join them.

I simply want to know what columns are common between the tables so I will know how to go ahead and join them to get the desired result.

Is there a way to know how to find the column names similar or do I have to check each and every table?

This is for SQL Server 2008

Answer 1

sys.foreign_keys will contain information about the columns which are explicitly related as keys.

Aside from that, there is no structural relationship in the schema between any given pair of columns. If any two columns on separate tables are supposed to be connected but aren't actually connected in the schema, that's more of a failure of the schema than anything else.

There is no mechanism which will reveal what columns the system's creators intended to be related but didn't actually relate.

Answer 2

My personal favorite is to look at column names if the FK method doesnt pan out.

SELECT c.name AS column_
, t.name AS table_

FROM sys.columns c
INNER JOIN sys.tables t
ON c.object_id = t.object_id
WHERE c.name LIKE '%userID%'
ORDER BY t.name