Stored Procs & Functions

Basit Nisar

I have 1 stored procedure that returns a Datetime value , I want to convert it into function so that i can call this function in multiple stored procedure? How can we do that?

4 Replies

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Naimish Makwana3y ago

Accepted answer

Hello Basit,

You can create function like below.

CREATE FUNCTION dbo.GetDateTime()
RETURNS Datetime
AS
BEGIN
    DECLARE @result Datetime
    
    -- Replace this with the code from your existing stored procedure
    SET @result = GETDATE()
    
    RETURN @result
END

Thanks

Naimish Makwana

Basit Nisar3y ago
Thanks very much fr help
Tuhin Paul3y ago
Hello Basit,

To convert your stored procedure that returns a datetime value into a function that can be called from multiple stored procedures, you can follow these steps:

1. Create a new function with the same name as your stored procedure and with the appropriate return type. like:
```
CREATE FUNCTION your_function_name ()
RETURNS datetime
AS
BEGIN
  -- Function body goes here
END
```
2. Now you should copy the body of your stored procedure into the body of your new function, making sure to remove any parameters that are no longer needed.

3. Replace any SELECT statements in the stored procedure with RETURN statements in the function. See below, lets assume your stored procedure looks like this:
```
CREATE PROCEDURE your_stored_procedure_name (@param1 int, @param2 int)
AS
BEGIN
  SELECT MAX(datetime_column) AS max_datetime
  FROM your_table_name
  WHERE column1 = @param1 AND column2 = @param2
END
```
You would convert it to a function :
```
CREATE FUNCTION your_function_name (@param1 int, @param2 int)
RETURNS datetime
AS
BEGIN
  DECLARE @max_datetime datetime
  
  SELECT @max_datetime = MAX(datetime_column)
  FROM your_table_name
  WHERE column1 = @param1 AND column2 = @param2
  
  RETURN @max_datetime
END
```
4. Modify your existing stored procedures to call the new function instead of the old stored procedure, passing any required parameters. like below:
```
CREATE PROCEDURE your_other_stored_procedure_name (@param1 int)
AS
BEGIN
  DECLARE @max_datetime datetime
  
  -- Call the function instead of the stored procedure
  SET @max_datetime = dbo.your_function_name(@param1)
  
  -- Rest of the stored procedure body goes here
END
```
With these changes, you should be able to call your new function from multiple stored procedures, passing in any required parameters, and returning a datetime value.

Amit Mohanty3y ago

Rewrite the stored procedure as a function, using the CREATE FUNCTION statement. The syntax of the CREATE FUNCTION statement is different from that of the CREATE PROCEDURE statement, so you will need to modify the code accordingly.
Example:

-- Original stored procedure
CREATE PROCEDURE dbo.GetCustomerName
    @CustomerID int,
    @FirstName varchar(50) OUTPUT,
    @LastName varchar(50) OUTPUT
AS
BEGIN
    SELECT @FirstName = FirstName, @LastName = LastName
    FROM Customers
    WHERE CustomerID = @CustomerID
END

-- Converted function
CREATE FUNCTION dbo.GetCustomerName
    (@CustomerID int)
RETURNS varchar(100)
AS
BEGIN
    DECLARE @FullName varchar(100)
    SELECT @FullName = FirstName + ' ' + LastName
    FROM Customers
    WHERE CustomerID = @CustomerID
    RETURN @FullName
END