SQL Server: Get table primary key using sql query [duplicate] - sql

Question

This question already has answers here:
How do you list the primary key of a SQL Server table?
(28 answers)
Closed 3 years ago.
I want to get a particular table's primary key using SQL query for SQL Server database.
In MySQL I am using following query to get table primary key:
SHOW KEYS FROM tablename WHERE Key_name = 'PRIMARY'
What is equivalent of above query for SQL Server ?.
If There is a query that will work for both MySQL and SQL Server then It will be an ideal case.

Answer 1

I also found another one for SQL Server:
SELECT COLUMN_NAME
FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE
WHERE OBJECTPROPERTY(OBJECT_ID(CONSTRAINT_SCHEMA + '.' + QUOTENAME(CONSTRAINT_NAME)), 'IsPrimaryKey') = 1
AND TABLE_NAME = 'TableName' AND TABLE_SCHEMA = 'Schema'

Answer 2

Found another one:
SELECT
KU.table_name as TABLENAME
,column_name as PRIMARYKEYCOLUMN
FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS AS TC
INNER JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE AS KU
ON TC.CONSTRAINT_TYPE = 'PRIMARY KEY'
AND TC.CONSTRAINT_NAME = KU.CONSTRAINT_NAME
AND KU.table_name='YourTableName'
ORDER BY
KU.TABLE_NAME
,KU.ORDINAL_POSITION
;
I have tested this on SQL Server 2003/2005

Answer 3

Using SQL SERVER 2005, you can try
SELECT i.name AS IndexName,
OBJECT_NAME(ic.OBJECT_ID) AS TableName,
COL_NAME(ic.OBJECT_ID,ic.column_id) AS ColumnName
FROM sys.indexes AS i INNER JOIN
sys.index_columns AS ic ON i.OBJECT_ID = ic.OBJECT_ID
AND i.index_id = ic.index_id
WHERE i.is_primary_key = 1
Found at SQL SERVER – 2005 – Find Tables With Primary Key Constraint in Database

Answer 4

From memory, it's either this
SELECT * FROM sys.objects
WHERE type = 'PK'
AND object_id = OBJECT_ID ('tableName')
or this..
SELECT * FROM sys.objects
WHERE type = 'PK'
AND parent_object_id = OBJECT_ID ('tableName')
I think one of them should probably work depending on how the data is stored
but I am afraid I have no access to SQL to actually verify the same.

Answer 5

SELECT COLUMN_NAME FROM {DATABASENAME}.INFORMATION_SCHEMA.KEY_COLUMN_USAGE
WHERE TABLE_NAME LIKE '{TABLENAME}' AND CONSTRAINT_NAME LIKE 'PK%'
WHERE
{DATABASENAME} = your database from your server AND
{TABLENAME} = your table name from which you want to see the primary key.
NOTE : enter your database name and table name without brackets.

Answer 6

select *
from sysobjects
where xtype='pk' and
parent_obj in (select id from sysobjects where name='tablename')
this will work in sql 2005

Answer 7

The code I'll give you works and retrieves not only keys, but a lot of data from a table in SQL Server. Is tested in SQL Server 2k5/2k8, dunno about 2k. Enjoy!
SELECT DISTINCT
sys.tables.object_id AS TableId,
sys.columns.column_id AS ColumnId,
sys.columns.name AS ColumnName,
sys.types.name AS TypeName,
sys.columns.precision AS NumericPrecision,
sys.columns.scale AS NumericScale,
sys.columns.is_nullable AS IsNullable,
( SELECT
COUNT(column_name)
FROM
INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE
WHERE
TABLE_NAME = sys.tables.name AND
CONSTRAINT_NAME =
( SELECT
constraint_name
FROM
INFORMATION_SCHEMA.TABLE_CONSTRAINTS
WHERE
TABLE_NAME = sys.tables.name AND
constraint_type = 'PRIMARY KEY' AND
COLUMN_NAME = sys.columns.name
)
) AS IsPrimaryKey,
sys.columns.max_length / 2 AS CharMaxLength /*BUG*/
FROM
sys.columns, sys.types, sys.tables
WHERE
sys.tables.object_id = sys.columns.object_id AND
sys.types.system_type_id = sys.columns.system_type_id AND
sys.types.user_type_id = sys.columns.user_type_id AND
sys.tables.name = 'TABLE'
ORDER BY
IsPrimaryKey
You can use only the primary key part, but I think that the rest might become handy.
Best regards,
David

Answer 8

This should list all the constraints and at the end you can put your filters
/* CAST IS DONE , SO THAT OUTPUT INTEXT FILE REMAINS WITH SCREEN LIMIT*/
WITH ALL_KEYS_IN_TABLE (CONSTRAINT_NAME,CONSTRAINT_TYPE,PARENT_TABLE_NAME,PARENT_COL_NAME,PARENT_COL_NAME_DATA_TYPE,REFERENCE_TABLE_NAME,REFERENCE_COL_NAME)
AS
(
SELECT CONSTRAINT_NAME= CAST (PKnUKEY.name AS VARCHAR(30)) ,
CONSTRAINT_TYPE=CAST (PKnUKEY.type_desc AS VARCHAR(30)) ,
PARENT_TABLE_NAME=CAST (PKnUTable.name AS VARCHAR(30)) ,
PARENT_COL_NAME=CAST ( PKnUKEYCol.name AS VARCHAR(30)) ,
PARENT_COL_NAME_DATA_TYPE= oParentColDtl.DATA_TYPE,
REFERENCE_TABLE_NAME='' ,
REFERENCE_COL_NAME=''
FROM sys.key_constraints as PKnUKEY
INNER JOIN sys.tables as PKnUTable
ON PKnUTable.object_id = PKnUKEY.parent_object_id
INNER JOIN sys.index_columns as PKnUColIdx
ON PKnUColIdx.object_id = PKnUTable.object_id
AND PKnUColIdx.index_id = PKnUKEY.unique_index_id
INNER JOIN sys.columns as PKnUKEYCol
ON PKnUKEYCol.object_id = PKnUTable.object_id
AND PKnUKEYCol.column_id = PKnUColIdx.column_id
INNER JOIN INFORMATION_SCHEMA.COLUMNS oParentColDtl
ON oParentColDtl.TABLE_NAME=PKnUTable.name
AND oParentColDtl.COLUMN_NAME=PKnUKEYCol.name
UNION ALL
SELECT CONSTRAINT_NAME= CAST (oConstraint.name AS VARCHAR(30)) ,
CONSTRAINT_TYPE='FK',
PARENT_TABLE_NAME=CAST (oParent.name AS VARCHAR(30)) ,
PARENT_COL_NAME=CAST ( oParentCol.name AS VARCHAR(30)) ,
PARENT_COL_NAME_DATA_TYPE= oParentColDtl.DATA_TYPE,
REFERENCE_TABLE_NAME=CAST ( oReference.name AS VARCHAR(30)) ,
REFERENCE_COL_NAME=CAST (oReferenceCol.name AS VARCHAR(30))
FROM sys.foreign_key_columns FKC
INNER JOIN sys.sysobjects oConstraint
ON FKC.constraint_object_id=oConstraint.id
INNER JOIN sys.sysobjects oParent
ON FKC.parent_object_id=oParent.id
INNER JOIN sys.all_columns oParentCol
ON FKC.parent_object_id=oParentCol.object_id /* ID of the object to which this column belongs.*/
AND FKC.parent_column_id=oParentCol.column_id/* ID of the column. Is unique within the object.Column IDs might not be sequential.*/
INNER JOIN sys.sysobjects oReference
ON FKC.referenced_object_id=oReference.id
INNER JOIN INFORMATION_SCHEMA.COLUMNS oParentColDtl
ON oParentColDtl.TABLE_NAME=oParent.name
AND oParentColDtl.COLUMN_NAME=oParentCol.name
INNER JOIN sys.all_columns oReferenceCol
ON FKC.referenced_object_id=oReferenceCol.object_id /* ID of the object to which this column belongs.*/
AND FKC.referenced_column_id=oReferenceCol.column_id/* ID of the column. Is unique within the object.Column IDs might not be sequential.*/
)
select * from ALL_KEYS_IN_TABLE
where
PARENT_TABLE_NAME in ('YOUR_TABLE_NAME')
or REFERENCE_TABLE_NAME in ('YOUR_TABLE_NAME')
ORDER BY PARENT_TABLE_NAME,CONSTRAINT_NAME;
For reference please read thru - http://blogs.msdn.com/b/sqltips/archive/2005/09/16/469136.aspx

Answer 9

Keep in mind that if you want to get exact primary field you need to put TABLE_NAME and TABLE_SCHEMA into the condition.
this solution should work:
select COLUMN_NAME from information_schema.KEY_COLUMN_USAGE
where CONSTRAINT_NAME='PRIMARY' AND TABLE_NAME='TABLENAME'
AND TABLE_SCHEMA='DATABASENAME'

Answer 10

It is also (Transact-SQL) ... according to BOL.
-- exec sp_serveroption 'SERVER NAME', 'data access', 'true' --execute once
EXEC sp_primarykeys #table_server = N'server_name',
#table_name = N'table_name',
#table_catalog = N'db_name',
#table_schema = N'schema_name'; --frequently 'dbo'