Procedure with optional parameters

  • I have a Procedure for search clients. User can give name, lastname, phone and so on but some of those might be Null. The procedure receive the optional @parameters. I have use the following query

    Select * FROM dbo.CLIENTS WHERE lastname = isnull(@prmlastname,lastname) and name=isnull(@prmname,name) and ... But of course will be more efficient some like:

    IF @prmlastname in null and @prmname is not null select * from dbo.clientes where name=@name but if a have 5 parametres it could be as much as 25 IFs and that is a lot of work.

    Other opcion Dinamic SQL but then I lost the precompiled caracteristic.

    What is the best solution?

    Is there any other solution for optional paramenters?

    Thanks for your help

  • The following example is straight out of "Books On Line"... modify it to handle your 5 nullable input parameters...

    D. Create a stored procedure using a parameter default of NULL

    The parameter default can be the value NULL. In this case, if you do not supply a parameter, SQL Server executes the stored procedure according to its other statements. No error message is displayed.

    The procedure definition can also specify that some other action be taken if you do not give a parameter. For example:

    CREATE PROC showind3 
           @table varchar(30) = NULL
    AS 
       IF @table IS NULL
       PRINT 'Give a table name'
    ELSE   
       SELECT TABLE_NAME = sysobjects.name,   
              INDEX_NAME = sysindexes.name, 
                INDEX_ID = indid   
         FROM sysindexes 
        INNER JOIN sysobjects   
                ON sysobjects.id = sysindexes.id   
        WHERE sysobjects.name = @table

    --Jeff Moden


    RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
    First step towards the paradigm shift of writing Set Based code:
    ________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.
    "Change is inevitable... change for the better is not".

    Helpful Links:
    How to post code problems
    How to Post Performance Problems
    Create a Tally Function (fnTally)
    Intro to Tally Tables and Functions

  • Federico,

    Read the following article by Erland Sommarskog, SQL Server MVP:

    http://www.sommarskog.se/dyn-search.html

    It's an in-depth article about this problem, with many solutions (using Dynamic SQL or Static SQL).

    Razvan

  • This SEEMS to work, but no guarantees!

    - john

     

    USE Northwind

    GO

    -- Demonstrate A Query Using An Optional Parameter

    CREATE PROCEDURE spGetOrders

       @OrderID INT = NULL

    AS

    BEGIN

       SELECT OrderID, CustomerID, EmployeeID, OrderDate

       FROM   Orders

       WHERE  OrderID =

          CASE 

             WHEN @OrderID IS NULL THEN OrderID   

             ELSE @OrderID

          END

       ORDER BY OrderID

    END

    GO

    -- Test:

    EXEC spGetOrders   -- Returns All Rows

    GO

    EXEC spGetOrders 10258 -- Returns 1 Row

    GO

  • (Update--continued from last post) Actually, I vaguely recall having "gotten burned" by some weird NULL-handling behavior in a query like this.  Things didn't always perform as expected. 

    Instead of testing against NULL, it might be safer if you hard-code a value for the optional parameter that you KNOW will never appear in the data -- e.g.,

    -- SAMPLE #2: Demonstrate A Query Using An Optional Parameter

    CREATE PROCEDURE spGetOrders2

       @OrderID INT = -9999

    AS

    BEGIN

       SELECT OrderID, CustomerID, EmployeeID, OrderDate

       FROM   Orders

       WHERE  OrderID =

          CASE 

             WHEN @OrderID = -9999 THEN OrderID   

             ELSE @OrderID

          END

       ORDER BY OrderID

    END

    GO

    -- Test:

    EXEC spGetOrders2             -- Returns All Rows

    GO

    EXEC spGetOrders2 10258       -- Returns One Row

    GO

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