?
Solved

multiple SELECT statements in a function

Posted on 2016-09-29
4
Medium Priority
?
79 Views
Last Modified: 2016-09-29
Hi,

I was wondering if it is possible to put multiple SELECT statements in a function.  What I want to do is to do something like this:

SELECT F1, F2, Fn('p1'), Fn('p2')
FROM table

Inside the function, different SELECT statements will be executed based on the parameter.  thanks
0
Comment
Question by:mcrmg
  • 2
4 Comments
 
LVL 56

Expert Comment

by:Ryan Chong
ID: 41821968
do you mean to create a table valued function?

Table-Valued User-Defined Functions
https://technet.microsoft.com/en-us/library/ms191165(v=sql.105).aspx

or for Fn and Fn you can define them as a normal Function in MS SQL

CREATE FUNCTION (Transact-SQL)
https://msdn.microsoft.com/en-us/library/ms186755.aspx
0
 

Author Comment

by:mcrmg
ID: 41821986
I want to see if it is possible to do this

BEGIN  
	DECLARE @LookupValue varchar(20)
	SET @LookupValue = ''
	
	SELECT @LookupValue = 
	CASE
	WHEN @input = 'abc' THEN

			SELECT @LookupValue = 
								case f1
									when '1' then 'yes'
									when '2' then 'no'   end

					FROM table
					where id = 123
	WHEN @input = 'xyz' THEN

			SELECT @LookupValue = 
								case f2
									when '1' then 'open'
									when '2' then 'close'   end

					FROM table
					where id = 123
	END 








     RETURN @LookupValue
end;
go

Open in new window

0
 
LVL 70

Accepted Solution

by:
Scott Pletcher earned 2000 total points
ID: 41822117
Yes, you can.  But, for efficiency, avoid using a local variable unless absolutely required:

CREATE FUNCTION function_name (
    @input varchar(10)
)
RETURNS varchar
AS
BEGIN
RETURN (
    SELECT CASE @input
        WHEN 'abc' THEN (
            SELECT case id when '1' then 'yes'
                                       when '2' then 'no' end
            FROM table_name
            WHERE id = 123
                  )
            WHEN 'xyz' THEN (
            SELECT case id when '1' then 'yes'
                                       when '2' then 'no' end
            FROM table_name
            WHERE id = 123
                  )
            END AS result
)
END /*FUNCTION*/
GO
0
 

Author Closing Comment

by:mcrmg
ID: 41822130
It works.  Thank you very much.
0

Featured Post

Keep up with what's happening at Experts Exchange!

Sign up to receive Decoded, a new monthly digest with product updates, feature release info, continuing education opportunities, and more.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Windocks is an independent port of Docker's open source to Windows.   This article introduces the use of SQL Server in containers, with integrated support of SQL Server database cloning.
This month, Experts Exchange sat down with resident SQL expert, Jim Horn, for an in-depth look into the makings of a successful career in SQL.
Via a live example, show how to backup a database, simulate a failure backup the tail of the database transaction log and perform the restore.
Viewers will learn how to use the INSERT statement to insert data into their tables. It will also introduce the NULL statement, to show them what happens when no value is giving for any given column.

588 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question