OPTION clause (Transact-SQL)
Applies to: 
SQL Server
Azure SQL Database
Azure SQL Managed Instance
Azure Synapse Analytics
Analytics Platform System (PDW)
SQL analytics endpoint in Microsoft Fabric
Warehouse in Microsoft Fabric
Specifies that the indicated query hint should be used throughout the entire query. Each query hint can be specified only one time, although multiple query hints are permitted. Only one OPTION clause can be specified with the statement.
This clause can be specified in the SELECT, DELETE, UPDATE, and MERGE statements.
Transact-SQL syntax conventions
Syntax
Syntax for SQL Server, Azure SQL Managed Instance, and Azure SQL Database:
[ OPTION ( <query_hint> [ , ...n ] ) ]
Syntax for Warehouse in Microsoft Fabric:
OPTION ( <query_option> [ , ...n ] )
<query_option> ::=
LABEL = label_name |
<query_hint>
<query_hint> ::=
HASH JOIN
| LOOP JOIN
| MERGE JOIN
| FORCE ORDER
| { FORCE | DISABLE } EXTERNALPUSHDOWN
| FOR TIMESTAMP AS OF '<point_in_time>'
Syntax for Azure Synapse Analytics and Analytics Platform System (PDW) and SQL analytics endpoint in Microsoft Fabric:
OPTION ( <query_option> [ , ...n ] )
<query_option> ::=
LABEL = label_name |
<query_hint>
<query_hint> ::=
HASH JOIN
| LOOP JOIN
| MERGE JOIN
| FORCE ORDER
| { FORCE | DISABLE } EXTERNALPUSHDOWN
Syntax for serverless SQL pool in Azure Synapse Analytics:
OPTION ( <query_option> [ , ...n ] )
<query_option> ::=
LABEL = label_name
Arguments
query_hint
Keywords that indicate which optimizer hints are used to customize the way the Database Engine processes the statement. For more information, see Query Hints.
Examples
The Transact-SQL code samples in this article use the AdventureWorks2022 or AdventureWorksDW2022 sample database, which you can download from the Microsoft SQL Server Samples and Community Projects home page.
A. Use an OPTION clause with a GROUP BY clause
The following example shows how the OPTION clause is used with a GROUP BY clause.
USE AdventureWorks2022;
GO
SELECT ProductID,
OrderQty,
SUM(LineTotal) AS Total
FROM Sales.SalesOrderDetail
WHERE UnitPrice < $5.00
GROUP BY ProductID, OrderQty
ORDER BY ProductID, OrderQty
OPTION (HASH GROUP, FAST 10);
GO
Examples: Azure Synapse Analytics and Analytics Platform System (PDW)
B. SELECT statement with a label in the OPTION clause
The following example shows an Azure Synapse Analytics SELECT statement with a label in the OPTION clause.
SELECT * FROM FactResellerSales
OPTION (LABEL = 'q17');
C. SELECT statement with a query hint in the OPTION clause
The following example shows a SELECT statement that uses a HASH JOIN query hint in the OPTION clause.
-- Uses AdventureWorks
SELECT COUNT(*) FROM dbo.DimCustomer a
INNER JOIN dbo.FactInternetSales b
ON (a.CustomerKey = b.CustomerKey)
OPTION (HASH JOIN);
D. SELECT statement with a label and multiple query hints in the OPTION clause
The following example is a Azure Synapse Analytics SELECT statement that contains a label and multiple query hints. When the query is run on the Compute nodes, SQL Server applies a hash join or merge join, according to the strategy that SQL Server decides is the most optimal.
SELECT COUNT(*) FROM dbo.DimCustomer a
INNER JOIN dbo.FactInternetSales b
ON (a.CustomerKey = b.CustomerKey)
OPTION (Label = 'CustJoin', HASH JOIN, MERGE JOIN);
E. Use a query hint when querying a view
The following example creates a view named CustomerView and then uses a HASH JOIN query hint in a query that references a view and a table.
CREATE VIEW CustomerView
AS
SELECT CustomerKey,
FirstName,
LastName
FROM ssawPDW..DimCustomer;
GO
SELECT COUNT(*)
FROM dbo.CustomerView a
INNER JOIN dbo.FactInternetSales b
ON (a.CustomerKey = b.CustomerKey)
OPTION (HASH JOIN);
GO
DROP VIEW CustomerView;
GO
F. Query with a subselect and a query hint
The following example shows a query that contains both a subselect and a query hint. The query hint is applied globally. Query hints can't be appended to the subselect statement.
CREATE VIEW CustomerView
AS
SELECT CustomerKey,
FirstName,
LastName
FROM ssawPDW..DimCustomer;
GO
SELECT *
FROM (
SELECT COUNT(*) AS a
FROM dbo.CustomerView a
INNER JOIN dbo.FactInternetSales b
ON (a.CustomerKey = b.CustomerKey)
) AS t
OPTION (HASH JOIN);
G. Force the join order to match the order in the query
The following example uses the FORCE ORDER hint to force the query plan to use the join order specified by the query. This hint improves performance on some queries, but not all queries.
This query obtains partition numbers, boundary values, boundary value types, and rows per boundary for the partitions in the ProspectiveBuyer table of the ssawPDW database.
SELECT sp.partition_number,
prv.value AS boundary_value,
lower(sty.name) AS boundary_value_type,
sp.rows
FROM sys.tables st
INNER JOIN sys.indexes si
ON st.object_id = si.object_id AND si.index_id < 2
INNER JOIN sys.partitions sp
ON sp.object_id = st.object_id AND sp.index_id = si.index_id
INNER JOIN sys.partition_schemes ps
ON ps.data_space_id = si.data_space_id
INNER JOIN sys.partition_range_values prv
ON prv.function_id = ps.function_id
INNER JOIN sys.partition_parameters pp
ON pp.function_id = ps.function_id
INNER JOIN sys.types sty
ON sty.user_type_id = pp.user_type_id AND prv.boundary_id = sp.partition_number
WHERE st.object_id = (
SELECT object_id
FROM sys.objects
WHERE name = 'FactResellerSales'
)
ORDER BY sp.partition_number
OPTION (FORCE ORDER);
H. Use EXTERNALPUSHDOWN
The following example forces the pushdown of the WHERE clause to the MapReduce job on the external Hadoop table.
SELECT ID FROM External_Table_AS A
WHERE ID < 1000000
OPTION (FORCE EXTERNALPUSHDOWN);
The following example prevents the pushdown of the WHERE clause to the MapReduce job on the external Hadoop table. All rows are returned to PDW where the WHERE clause is applied.
SELECT ID FROM External_Table_AS A
WHERE ID < 10
OPTION (DISABLE EXTERNALPUSHDOWN);
I. Query data as of a point in time
Applies to: Warehouse in Microsoft Fabric
For more information, see FOR TIMESTAMP query hint.
Use the TIMESTAMP syntax in the OPTION clause to query data as it existed in the past, in Synapse Data Warehouse in Microsoft Fabric. The following sample query returns data as it appeared on March 13, 2024 at 7:39:35.28 PM UTC. The time zone is always in UTC.
SELECT OrderDateKey,
SUM(SalesAmount) AS TotalSales
FROM FactInternetSales
GROUP BY OrderDateKey
ORDER BY OrderDateKey
OPTION (FOR TIMESTAMP AS OF '2024-03-13T19:39:35.28');--March 13, 2024 at 7:39:35.28 PM UTC