How to find all the foreign key constraints in a database

Hi experts,

I have a requirement for my db where I need to find all the foreign key constraints in my db. How can I do so ?

shawn said:

Hi experts,

I have a requirement for my db where I need to find all the foreign key constraints in my db. How can I do so ?

 

Hi Shawn,

use this query to find all foreign key in database. simply run the following query:

SELECT 
    FK_Table  = FK.TABLE_NAME, 
    FK_Column = CU.COLUMN_NAME, 
    PK_Table  = PK.TABLE_NAME, 
    PK_Column = PT.COLUMN_NAME, 
    Constraint_Name = C.CONSTRAINT_NAME 
FROM 
    INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS C 
    INNER JOIN 
    INFORMATION_SCHEMA.TABLE_CONSTRAINTS FK 
        ON C.CONSTRAINT_NAME = FK.CONSTRAINT_NAME 
    INNER JOIN 
    INFORMATION_SCHEMA.TABLE_CONSTRAINTS PK 
        ON C.UNIQUE_CONSTRAINT_NAME = PK.CONSTRAINT_NAME 
    INNER JOIN 
    INFORMATION_SCHEMA.KEY_COLUMN_USAGE CU 
        ON C.CONSTRAINT_NAME = CU.CONSTRAINT_NAME 
    INNER JOIN 
    ( 
        SELECT 
            i1.TABLE_NAME, i2.COLUMN_NAME 
        FROM 
            INFORMATION_SCHEMA.TABLE_CONSTRAINTS i1 
            INNER JOIN 
            INFORMATION_SCHEMA.KEY_COLUMN_USAGE i2 
            ON i1.CONSTRAINT_NAME = i2.CONSTRAINT_NAME 
            WHERE i1.CONSTRAINT_TYPE = 'PRIMARY KEY' 
    ) PT 
    ON PT.TABLE_NAME = PK.TABLE_NAME 
-- optional: 
ORDER BY 
    1,2,3,4