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Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support. Pass parameters to a SQL Server stored procedure
In this articleThis article introduces an example of passing parameters to a SQL Server stored procedure from Visual FoxPro. Original product version: Visual FoxPro SummaryThere are two ways to pass parameters to a stored procedure using SQLExec. One way, which works across all versions of Visual FoxPro, is to build the SQL command as a string variable. The advantage of this method is that you can check the string and see exactly which SQL command you are passing to the back end. The other way is to pass the Foxpro variables preceded with question marks, as in a parameterized view. In Visual FoxPro version 5.0 and later versions, this allows you to obtain values from the stored procedure that are being returned as output parameters. More informationFollow these steps:
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Specify Parameters
In this articleApplies to: SQL Server (all supported versions) Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW) By specifying procedure parameters, calling programs are able to pass values into the body of the procedure. Those values can be used for a variety of purposes during procedure execution. Procedure parameters can also return values to the calling program if the parameter is marked as an OUTPUT parameter. A procedure can have a maximum of 2100 parameters; each assigned a name, data type, and direction. Optionally, parameters can be assigned default values. The following section provides information about passing values into parameters and about how each of the parameter attributes is used during a procedure call. Passing Values into ParametersThe parameter values supplied with a procedure call must be constants or a variable; a function name cannot be used as a parameter value. Variables can be user-defined or system variables such as @@spid. The following examples demonstrate passing parameter values to the procedure uspGetWhereUsedProductID. They illustrate how to pass parameters as constants and variables and also how to use a variable to pass the value of a function. USE AdventureWorks2012; GO -- Passing values as constants. EXEC dbo.uspGetWhereUsedProductID 819, '20050225'; GO -- Passing values as variables. DECLARE @ProductID int, @CheckDate datetime; SET @ProductID = 819; SET @CheckDate = '20050225'; EXEC dbo.uspGetWhereUsedProductID @ProductID, @CheckDate; GO -- Try to use a function as a parameter value. -- This produces an error message. EXEC dbo.uspGetWhereUsedProductID 819, GETDATE(); GO -- Passing the function value as a variable. DECLARE @CheckDate datetime; SET @CheckDate = GETDATE(); EXEC dbo.uspGetWhereUsedProductID 819, @CheckDate; GOSpecifying Parameter NamesWhen creating a procedure and declaring a parameter name, the parameter name must begin with a single @ character and must be unique in the scope of the procedure. Explicitly naming the parameters and assigning the appropriate values to each parameter in a procedure call allows the parameters to be supplied in any order. For example, if the procedure my_proc expects three parameters named @first, @second, and @third, the values passed to the procedure can be assigned to the parameter names, such as: EXECUTE my_proc @second = 2, @first = 1, @third = 3; Note If one parameter value is supplied in the form @parameter =value, all subsequent parameters must be supplied in this manner. If the parameter values are not passed in the form @parameter =value, the values must be supplied in the identical order (left to right) as the parameters are listed in the CREATE PROCEDURE statement. Warning Any parameter passed in the form @parameter =value with the parameter misspelled, will cause SQL Server to generate an error and prevent procedure execution. Specifying Parameter Data TypesParameters must be defined with a data type when they are declared in a CREATE PROCEDURE statement. The data type of a parameter determines the type and range of values that are accepted for the parameter when the procedure is called. For example, if you define a parameter with a tinyint data type, only numeric values ranging from 0 to 255 are accepted when passed into that parameter. An error is returned if a procedure is executed with a value incompatible with the data type. Specifying Parameter Default ValuesA parameter is considered optional if the parameter has a default value specified when it is declared. It is not necessary to provide a value for an optional parameter in a procedure call. The default value of a parameter is used when:
Note If the default value is a character string that contains embedded blanks or punctuation, or if it starts with a number (for example, 6xxx), it must be enclosed in single, straight quotation marks. Note Default parameters are not supported in Azure Synapse Analytics or Parallel Data Warehouse. If no value can be specified appropriately as a default for the parameter, specify NULL as the default. It is a good idea to have the procedure return a customized message if the procedure is executed without a value for the parameter. The following example creates the uspGetSalesYTD procedure with one input parameter, @SalesPerson. NULL is assigned as the default value for the parameter and is used in error handling statements to return a custom error message for cases when the procedure is executed without a value for the @SalesPerson parameter. USE AdventureWorks2012; GO IF OBJECT_ID('Sales.uspGetSalesYTD', 'P') IS NOT NULL DROP PROCEDURE Sales.uspGetSalesYTD; GO CREATE PROCEDURE Sales.uspGetSalesYTD @SalesPerson nvarchar(50) = NULL -- NULL default value AS SET NOCOUNT ON; -- Validate the @SalesPerson parameter. IF @SalesPerson IS NULL BEGIN PRINT 'ERROR: You must specify the last name of the sales person.' RETURN END -- Get the sales for the specified sales person and -- assign it to the output parameter. SELECT SalesYTD FROM Sales.SalesPerson AS sp JOIN HumanResources.vEmployee AS e ON e.BusinessEntityID = sp.BusinessEntityID WHERE LastName = @SalesPerson; RETURN GOThe following example executes the procedure. The first statement executes the procedure without specifying an input value. This causes the error handling statements in the procedure to return the custom error message. The second statement supplies an input value and returns the expected result set. -- Run the procedure without specifying an input value. EXEC Sales.uspGetSalesYTD; GO -- Run the procedure with an input value. EXEC Sales.uspGetSalesYTD N'Blythe'; GOAlthough parameters for which defaults have been supplied can be omitted, the list of parameters can only be truncated. For example, if a procedure has five parameters, both the fourth and the fifth parameters can be omitted. However the fourth parameter cannot be skipped as long as the fifth parameter is included, unless the parameters are supplied in the form @parameter =value. Specifying Parameter DirectionThe direction of a parameter is either input, a value is passed into the body of the procedure, or output, the procedure returns a value to the calling program. The default is an input parameter. To specify an output parameter, the OUTPUT keyword must be specified in the definition of the parameter in the CREATE PROCEDURE statement. The procedure returns the current value of the output parameter to the calling program when the procedure exits. The calling program must also use the OUTPUT keyword when executing the procedure to save the parameter's value in a variable that can be used in the calling program. The following example creates the Production.usp_GetList procedure, which returns a list of products that have prices that do not exceed a specified amount. The example shows using multiple SELECT statements and multiple OUTPUT parameters. OUTPUT parameters allow an external procedure, a batch, or more than one Transact-SQL statement to access a value set during the procedure execution. USE AdventureWorks2012; GO IF OBJECT_ID ( 'Production.uspGetList', 'P' ) IS NOT NULL DROP PROCEDURE Production.uspGetList; GO CREATE PROCEDURE Production.uspGetList @Product varchar(40) , @MaxPrice money , @ComparePrice money OUTPUT , @ListPrice money OUT AS SET NOCOUNT ON; SELECT p.[Name] AS Product, p.ListPrice AS 'List Price' FROM Production.Product AS p JOIN Production.ProductSubcategory AS s ON p.ProductSubcategoryID = s.ProductSubcategoryID WHERE s.[Name] LIKE @Product AND p.ListPrice < @MaxPrice; -- Populate the output variable @ListPprice. SET @ListPrice = (SELECT MAX(p.ListPrice) FROM Production.Product AS p JOIN Production.ProductSubcategory AS s ON p.ProductSubcategoryID = s.ProductSubcategoryID WHERE s.[Name] LIKE @Product AND p.ListPrice < @MaxPrice); -- Populate the output variable @compareprice. SET @ComparePrice = @MaxPrice; GOExecute usp_GetList to return a list of Adventure Works products (Bikes) that cost less than $700. The OUTPUT parameters @cost and @compareprices are used with control-of-flow language to return a message in the Messages window. Note The OUTPUT variable must be defined during the procedure creation and also during the use of the variable. The parameter name and variable name do not have to match. However, the data type and parameter positioning must match (unless @listprice= variable is used). DECLARE @ComparePrice money, @Cost money ; EXECUTE Production.uspGetList '%Bikes%', 700, @ComparePrice OUT, @Cost OUTPUT IF @Cost <= @ComparePrice BEGIN PRINT 'These products can be purchased for less than $'+RTRIM(CAST(@ComparePrice AS varchar(20)))+'.' END ELSE PRINT 'The prices for all products in this category exceed $'+ RTRIM(CAST(@ComparePrice AS varchar(20)))+'.';Here is the partial result set: Product List Price -------------------------------------------------- ------------------ Road-750 Black, 58 539.99 Mountain-500 Silver, 40 564.99 Mountain-500 Silver, 42 564.99 ... Road-750 Black, 48 539.99 Road-750 Black, 52 539.99 (14 row(s) affected) These items can be purchased for less than $700.00.See AlsoCREATE PROCEDURE (Transact-SQL) FeedbackSubmit and view feedback for How do you pass a parameter to a procedure?To pass one or more arguments to a procedure
In the calling statement, follow the procedure name with parentheses. Inside the parentheses, put an argument list. Include an argument for each required parameter the procedure defines, and separate the arguments with commas.
Can we pass parameters to stored procedures?You can also pass parameters to a stored procedure, so that the stored procedure can act based on the parameter value(s) that is passed.
How do I pass a stored procedure parameter in SQL?There are two ways to pass parameters to a stored procedure using SQLExec. One way, which works across all versions of Visual FoxPro, is to build the SQL command as a string variable. The advantage of this method is that you can check the string and see exactly which SQL command you are passing to the back end.
How do you call a stored procedure with parameters?Expand the database that you want, expand Programmability, and then expand Stored Procedures. Right-click the user-defined stored procedure that you want and select Execute Stored Procedure. In the Execute Procedure dialog box, specify a value for each parameter and whether it should pass a null value.
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