Using EXEC inside SELECT statement in SQL Server - sql

Question

I need to use exec inside of select clause. The query for the exec is created according to the columns of the table to on which select clause if used. What i want to do is something like following:
SELECT distinct
MTMain.[TableName],
MTMain.[TableFKey],
(select IsActive (exec GetStringForIsActive MTMain.[TableName],MTMain.[TableFKey]))
FROM
[MasterTableForLanguage] MTMain
Here, GetStringForIsActive is the stored procedure I want to execute for every row selected from MasterTableForLanguage.
The stored procedure will use EXEC to execute the following string
select IsActive from [TableName] where PKID= cast([TableFKey] as int)
TableName and TableFKey will be inputs of the stored procedure.

Answer 1

If you can modify your Stored Procedure GetStringForIsActive to return TableName, TableFKey and IsActive, you can use a cursor to get execute it for each row and add the results to a temp table.
ie:
exec GetStringForIsActive 'TableName', 'TableFKey'
returns
select [TableName], [TableFKey], IsActive from [TableName] where PKID= cast([TableFKey] as int)
The code would be like this:
declare #TableName nvarchar(50)
declare #TableFKey nvarchar(50)
declare #Results table (TableName nvarchar(50), TableFKey nvarchar(50), IsActive bit)
declare TableCursor cursor fast_forward for
select TableName, TableFKey from MasterTableForLanguage
open TableCursor
fetch next from TableCursor into #TableName, #TableFKey
if ##FETCH_STATUS <> -1
print 'MasterTableForLanguage check'
while (##FETCH_STATUS <> -1)
begin
insert into #Results
exec GetStringForIsActive #TableName, #TableFKey
fetch next from TableCursor into #TableName, #TableFKey
end
close TaleCursor
deallocate TableCursor
select * from #Results

Answer 2

use Functions instead of Stored procedures in SELECT clause.
Edited:
create that function
CREATE FUNCTION function1 (#TableName nvarchar(10),#TableFKey nvarchar(10))
RETURNS nvarchar(100) AS
BEGIN
-- do whatever here
END
then
SELECT distinct
MTMain.[TableName],
MTMain.[TableFKey],
function1(MTMain.[TableName],MTMain.[TableFKey])
FROM
[MasterTableForLanguage] MTMain
Does this make sense?

Answer 3

Well, I think to answer the full question, I don't believe a stored procedure would EXEC a SELECT statement, it would simply perform the SELECT.
You EXEC your current proc and pass it vars, and it returns a value BASED ON the select statement it runs. It's not EXEC'ing that statement, simply performing a select. I have several stored procs I use daily in some SQL agent processes, they all perform selects to query various tables, and none of them call an EXEC to perform those actions. This is my own example:
CREATE PROCEDURE [myproc]
#job_ident INT
AS
BEGIN
SET NOCOUNT ON;
...
SELECT TOP(1) #filter_type = filter_type FROM [place] WHERE [ident] = #job_ident
...
END
As mentioned previously, the most effective way to perform your query would be to perform that select inside a function, something similar to this I think will do:
CREATE FUNCTION ThisFunction (
#TableName nvarchar(10),
#TableFKey nvarchar(10)
)
RETURNS nvarchar(100)
AS
BEGIN
RETURN
(
select IsActive from [TableName] where PKID= cast([TableFKey] as int)
)
END
You could then do exactly as you want...
SELECT distinct
MTMain.[TableName],
MTMain.[TableFKey],
ThisFunction(MTMain.[TableName],MTMain.[TableFKey])
FROM
[MasterTableForLanguage] MTMain