How to Find Out What Foreign Key Constraint References a Table in SQL Server

How can I list all foreign keys referencing a given table in SQL Server?

Not sure why no one suggested but I use sp_fkeys to query foreign keys for a given table:

EXEC sp_fkeys 'TableName'

You can also specify the schema:

EXEC sp_fkeys @pktable_name = 'TableName', @pktable_owner = 'dbo'

Without specifying the schema, the docs state the following:

If pktable_owner is not specified, the default table visibility rules
of the underlying DBMS apply.

In SQL Server, if the current user owns a table with the specified
name, that table's columns are returned. If pktable_owner is not
specified and the current user does not own a table with the specified
pktable_name, the procedure looks for a table with the specified
pktable_name owned by the database owner. If one exists, that table's
columns are returned.

How can I find out what FOREIGN KEY constraint references a table in SQL Server?

Here it is:

SELECT 
OBJECT_NAME(f.parent_object_id) TableName,
COL_NAME(fc.parent_object_id,fc.parent_column_id) ColName
FROM
sys.foreign_keys AS f
INNER JOIN
sys.foreign_key_columns AS fc
ON f.OBJECT_ID = fc.constraint_object_id
INNER JOIN
sys.tables t
ON t.OBJECT_ID = fc.referenced_object_id
WHERE
OBJECT_NAME (f.referenced_object_id) = 'YourTableName'

This way, you'll get the referencing table and column name.

Edited to use sys.tables instead of generic sys.objects as per comment suggestion.
Thanks, marc_s

How to find foreign key dependencies in SQL Server?

The following query will help to get you started. It lists all Foreign Key Relationships within the current database.

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

You can also view relationships graphically within SQL Server Management studio within Database Diagrams.

How can I list all foreign keys in a Table?

The below code snippet could be put to some use and modified by your further requirement -
This would pull the column level details such as data type, length, precision, scale etc...

SELECT  obj.name AS FK_NAME,
sch.name AS [schema_name],
tab1.name AS [table],
col1.name AS [column],
tab2.name AS [referenced_table],
col2.name AS [referenced_column],
TY.[name] AS system_data_type, col1.[max_length],col1.[precision], col1.[scale], col1.[is_nullable], col1.[is_ansi_padded]
FROM sys.foreign_key_columns fkc
INNER JOIN sys.objects obj
ON obj.object_id = fkc.constraint_object_id
INNER JOIN sys.tables tab1
ON tab1.object_id = fkc.parent_object_id
INNER JOIN sys.schemas sch
ON tab1.schema_id = sch.schema_id
INNER JOIN sys.columns col1
ON col1.column_id = parent_column_id AND col1.object_id = tab1.object_id
INNER JOIN sys.tables tab2
ON tab2.object_id = fkc.referenced_object_id
INNER JOIN sys.columns col2
ON col2.column_id = referenced_column_id AND col2.object_id = tab2.object_id
INNER JOIN sys.[types] TY ON col1.[system_type_id] = TY.[system_type_id] AND col1.[user_type_id] = TY.[user_type_id]
AND tab1.name = 'TableName1'

Find all foreign keys constraints in database referencing a certain primary key

Look at How to find foreign key dependencies in SQL Server?

You can sort on PK_Table and PK_Column to get what you want

Selecting all foreign key references on table

You may use this query to find all foreign key references on a table:

SELECT 
fk.owner fk_schema_owner,fk.table_name fk_table,
fk.column_name fk_column, fk.constraint_name fk_constraint_name,
pk.r_owner pk_schema_owner,
c_pk.table_name pk_table_name, c_pk.constraint_name pk_constraint_name
FROM
all_cons_columns fk
JOIN all_constraints pk
ON fk.owner = pk.owner AND fk.constraint_name = pk.constraint_name
JOIN all_constraints c_pk
ON pk.r_owner = c_pk.owner AND pk.r_constraint_name = c_pk.constraint_name
WHERE pk.constraint_type = 'R' AND fk.table_name = :InputTableName

How do I see all foreign keys to a table or column?

For a Table:

SELECT 
TABLE_NAME,COLUMN_NAME,CONSTRAINT_NAME, REFERENCED_TABLE_NAME,REFERENCED_COLUMN_NAME
FROM
INFORMATION_SCHEMA.KEY_COLUMN_USAGE
WHERE
REFERENCED_TABLE_SCHEMA = '<database>' AND
REFERENCED_TABLE_NAME = '<table>';

For a Column:

SELECT 
TABLE_NAME,COLUMN_NAME,CONSTRAINT_NAME, REFERENCED_TABLE_NAME,REFERENCED_COLUMN_NAME
FROM
INFORMATION_SCHEMA.KEY_COLUMN_USAGE
WHERE
REFERENCED_TABLE_SCHEMA = '<database>' AND
REFERENCED_TABLE_NAME = '<table>' AND
REFERENCED_COLUMN_NAME = '<column>';

Basically, we changed REFERENCED_TABLE_NAME with REFERENCED_COLUMN_NAME in the where clause.

Is it possible to list all foreign keys in a database?

I use this statement, it seems to work pretty well.

SELECT RC.CONSTRAINT_NAME FK_Name
, KF.TABLE_SCHEMA FK_Schema
, KF.TABLE_NAME FK_Table
, KF.COLUMN_NAME FK_Column
, RC.UNIQUE_CONSTRAINT_NAME PK_Name
, KP.TABLE_SCHEMA PK_Schema
, KP.TABLE_NAME PK_Table
, KP.COLUMN_NAME PK_Column
, RC.MATCH_OPTION MatchOption
, RC.UPDATE_RULE UpdateRule
, RC.DELETE_RULE DeleteRule
FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS RC
JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE KF ON RC.CONSTRAINT_NAME = KF.CONSTRAINT_NAME
JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE KP ON RC.UNIQUE_CONSTRAINT_NAME = KP.CONSTRAINT_NAME


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