use-table-valued-parameters-database-engine.md

title	Use Table-Valued Parameters (Database Engine) | Microsoft Docs
ms.custom
ms.date	03/16/2017
ms.prod	sql-server-2016
ms.reviewer
ms.suite
ms.technology	dbe-tables
ms.tgt_pltfrm
ms.topic	article
helpviewer_keywords	table-valued parameters table-valued parameters, about table-valued parameters parameters [SQL Server], table-valued TVP See table-valued parameters
ms.assetid	5e95a382-1e01-4c74-81f5-055612c2ad99
caps.latest.revision	31
author	BYHAM
ms.author	rickbyh
manager	jhubbard

Use Table-Valued Parameters (Database Engine)

[!INCLUDEtsql-appliesto-ss2016-all_md]

Table-valued parameters are declared by using user-defined table types. You can use table-valued parameters to send multiple rows of data to a [!INCLUDEtsql] statement or a routine, such as a stored procedure or function, without creating a temporary table or many parameters.

Table-valued parameters are like parameter arrays in OLE DB and ODBC, but offer more flexibility and closer integration with [!INCLUDEtsql]. Table-valued parameters also have the benefit of being able to participate in set-based operations.

[!INCLUDEtsql] passes table-valued parameters to routines by reference to avoid making a copy of the input data. You can create and execute [!INCLUDEtsql] routines with table-valued parameters, and call them from [!INCLUDEtsql] code, managed and native clients in any managed language.

In This Topic:

Benefits

Restrictions

Table-Valued Parameters vs. BULK INSERT Operations

Example

Benefits

A table-valued parameter is scoped to the stored procedure, function, or dynamic [!INCLUDEtsql] text, exactly like other parameters. Similarly, a variable of table type has scope like any other local variable that is created by using a DECLARE statement. You can declare table-valued variables within dynamic [!INCLUDEtsql] statements and pass these variables as table-valued parameters to stored procedures and functions.

Table-valued parameters offer more flexibility and in some cases better performance than temporary tables or other ways to pass a list of parameters. Table-valued parameters offer the following benefits:

• Do not acquire locks for the initial population of data from a client.

• Provide a simple programming model.

• Enable you to include complex business logic in a single routine.

• Reduce round trips to the server.

• Can have a table structure of different cardinality.

• Are strongly typed.

• Enable the client to specify sort order and unique keys.

• Are cached like a temp table when used in a stored procedure. Starting with [!INCLUDEssSQL11], table-valued parameters are also cached for parameterized queries.

Restrictions

Table-valued parameters have the following restrictions:

• [!INCLUDEssNoVersion] does not maintain statistics on columns of table-valued parameters.

• Table-valued parameters must be passed as input READONLY parameters to [!INCLUDEtsql] routines. You cannot perform DML operations such as UPDATE, DELETE, or INSERT on a table-valued parameter in the body of a routine.

• You cannot use a table-valued parameter as target of a SELECT INTO or INSERT EXEC statement. A table-valued parameter can be in the FROM clause of SELECT INTO or in the INSERT EXEC string or stored procedure.

Table-Valued Parameters vs. BULK INSERT Operations

Using table-valued parameters is comparable to other ways of using set-based variables; however, using table-valued parameters frequently can be faster for large data sets. Compared to bulk operations that have a greater startup cost than table-valued parameters, table-valued parameters perform well for inserting less than 1000 rows.

Table-valued parameters that are reused benefit from temporary table caching. This table caching enables better scalability than equivalent BULK INSERT operations. By using small row-insert operations a small performance benefit might be gained by using parameter lists or batched statements instead of BULK INSERT operations or table-valued parameters. However, these methods are less convenient to program, and performance decreases quickly as rows increase.

Table-valued parameters perform equally well or better than an equivalent parameter array implementation.

Example

The following example uses [!INCLUDEtsql] and shows you how to create a table-valued parameter type, declare a variable to reference it, fill the parameter list, and then pass the values to a stored procedure.

USE AdventureWorks2012;  
GO  
  
/* Create a table type. */  
CREATE TYPE LocationTableType AS TABLE   
( LocationName VARCHAR(50)  
, CostRate INT );  
GO  
  
/* Create a procedure to receive data for the table-valued parameter. */  
CREATE PROCEDURE dbo. usp_InsertProductionLocation  
    @TVP LocationTableType READONLY  
    AS   
    SET NOCOUNT ON  
    INSERT INTO AdventureWorks2012.Production.Location  
           (Name  
           ,CostRate  
           ,Availability  
           ,ModifiedDate)  
        SELECT *, 0, GETDATE()  
        FROM  @TVP;  
        GO  
  
/* Declare a variable that references the type. */  
DECLARE @LocationTVP AS LocationTableType;  
  
/* Add data to the table variable. */  
INSERT INTO @LocationTVP (LocationName, CostRate)  
    SELECT Name, 0.00  
    FROM AdventureWorks2012.Person.StateProvince;  
  
/* Pass the table variable data to a stored procedure. */  
EXEC usp_InsertProductionLocation @LocationTVP;  
GO  

See Also

CREATE TYPE (Transact-SQL)
DECLARE @local_variable (Transact-SQL)
sys.types (Transact-SQL)
sys.parameters (Transact-SQL)
sys.parameter_type_usages (Transact-SQL)
CREATE PROCEDURE (Transact-SQL)
CREATE FUNCTION (Transact-SQL)