Dynamic parameters from a table

try to dynamically get variable NAMES from a table (not the values of the variables, but rather their names), and execute a program with the variables e.g. exec my_sp with a parameter from a table (e.g. @JobID). The actual value of the variable is in the program, and only the name of the variable is taken from a table, but instead of passing the variable's value, the sp passes the variable's name. Is it possible somehow?
Thank you!

Here is the ocde:
Values in table ProgParams:
ProgID (int) ,Parameter (varchar(50))
1      @JobID
2      @FileName
3      @FilePath

SET @JobID=1
SET @Program = 'myprogram.exe'
SELECT Parameter FROM ProgParams WHERE ProgID=@progID
FETCH NEXT FROM my_cursor INTO @Param
SET @FullCommand = '@Program'+' '+RTRIM(@Param)
EXEC master..xp_cmdshell @FullCommand
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isrsaAuthor Commented:
I have only 40 points, but I will increase it tomorrow when I get more.
Yes. This should work.

If command below did not work

EXEC master..xp_cmdshell @FullCommand

Then Try

SET @FullCommand = '@Program'+' '+RTRIM(@Param)
SET @cmd = 'echo ' + @FullCommand + ' > c:\mycommand.bat'
EXEC master..xp_cmdshell @cmd
EXEC master..xp_cmdshell 'c:\mycommand.bat'


Namasi Navaretnam
isrsaAuthor Commented:
What should be in mycommand.bat, or is it just a sample name, and I can run myprogram.exe instead?
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isrsaAuthor Commented:
Sorry, I got it.
I should echo the command to a batch file. Let me try it.
isrsaAuthor Commented:
Well, the problem still occurs.
My problem is not to run a program but to pass the variable value, and not its name.
Declare @cmd varchar(100), @Prog varchar(50), @outer varchar(50)
Set @Prog = 'notepad '
Set @outer = '@Prog'
SET @cmd='echo '+@outer+' >c:\mycmd.bat'
EXEC master..xp_cmdshell @cmd
EXEC master..xp_cmdshell 'c:\mycmd.bat'

I want it to execute notepad, and I have the variable name (@Prog) only as a varchar(50) (because I retrieve it from a table.).

Thank you so much!
Declare @cmd varchar(100), @Prog varchar(50), @outer varchar(50)
Set @Prog = 'notepad '
Set @outer = '''' +  @Parm + ''''
SET @cmd='echo '+ @prog +  '  ' +  @outer  ' >c:\mycmd.bat'
EXEC master..xp_cmdshell @cmd
EXEC master..xp_cmdshell 'c:\mycmd.bat'

Ultimately you want to output the actual command into c:\mycmd.bat file. The command line may or may not have args.


MyProgram.exe Parm1, Param2 , etc


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isrsaAuthor Commented:
It works. I will accept your answer later.
Thank you very very much.
isrsaAuthor Commented:
I had a mistake. When running the following code:

Declare @cmd varchar(100), @Prog varchar(50), @outer varchar(50), @Param varchar(50), @Id varchar(20)
set @Id='A3499'
set @Param = '@id'
Set @Prog = 'notepad '
Set @outer = '''' +  @Param + ''''
SET @cmd='echo '+ @prog +  '  ' +  @outer  ' >c:\mycmd.bat'
EXEC master..xp_cmdshell @cmd
EXEC master..xp_cmdshell 'c:\mycmd.bat'

I still get the error:
Server: Msg 170, Level 15, State 1, Line 6
Line 6: Incorrect syntax near ' >c:\mycmd.bat'.
Missing a plus sign

SET @cmd='echo '+ @prog +  '  ' +  @outer +  ' >c:\mycmd.bat'


isrsaAuthor Commented:
I'm back to the first problem. It sends to the batch file the command 'notepad '@id'', instead of 'notepad A3499' as I want.
Thank you so much!

SET @cmd='echo '+ @prog +  '  ' +  @outer +  ' >c:\mycmd.bat'

In the command above make sure @prog  is set as notepad and @outer  is set as 'A3499'

isrsaAuthor Commented:
That's the whole point. I get the variable NAME from a table, not its value. From my point of view @outer doesn't and cannot know what value @id holds because @id comes as a varchar from a table (as: '@id').
Is there any way that the code I posted on:11/04/2003 11:13AM PST will send the batch file the VALUE that @id holds (having only '@id' as a varchar)?
Is is possible to get a value if @id using dynamic sql?

create table #temp (col1 varchar(100))
execute sp_executesql
          N'insert #temp select max(emp_id) from pubs.dbo.employee'

select col1 from #temp
drop table #temp

There are few examples in the help file.
isrsaAuthor Commented:
First, thank you so much for your replies. I really appreciate it.
Second, let me explain. The reason I am trying to achieve this is because the program I am writing is a scheduler that will run various programs that might need parameters.
The scheduler has all the possible parameters that those programs might need (well, almost everything), but it does not know which program needs what parameters.
Because the programs that the scheduler runs are replaceable (new versions, etc.), I would like to have dynamic parameters, which means that if I decide to replace a program that takes emp_id, job_id, and file_name with one that takes only emp_id, and file_name, I should not have to change the code, but rather only the parameters names in a table (as: prog_id-1 parameter-emp_id, task_id-1 parameter-job_id, task_id-2 parameter-file_name, etc.).
Of course, I can "hard code" the parameters directly in my code (“if @prog_id=1 set @parameters=emp_id+' '+job_id”), but I am trying to achieve a more dynamic program.
I hope that I was clear enough.
Thank you very much.
isrsaAuthor Commented:
I was not clear about the table. I mean something like this:
prog_id (int), parameter (varchar(50))
1, '@Job_ID'
1, '@Emp_ID'
2, '@File_Name'
2, '@In_Date'
2, '@Out_Date'
3, 'c:\workdir'
3, '@Rec_No'
3, 'd:\workdir\web_in'

Now in the program I want to select:
'SELECT parameter FROM progs WHERE prog_id=@prog_id'
into a cursor or a temporary table, then loop through the results, and run each program with its parameters.
DECLARE @v_paralist varchar(8000),
        @v_paravaluelist varchar(8000),
        @v_prog_id  varchar(30),
        @v_parameter varchar(100),
        @v_paravalue varchar(100)

SELECT parameter FROM progs WHERE prog_id=@v_prog_id

select @v_paralist = ' ', @v_paravaluelist = ' '

OPEN table_cursor

FETCH NEXT FROM table_cursor
INTO @v_paramter

   select @v_paralist = @v_paralist + @v_parameter + ', '

    get the value of parameter using sp_execute_sql
    See example in the help file.

   select @v_paravaluelist = @v_paravaluelist + @v_paravalue + ', '

   FETCH NEXT FROM table_cursor
   INTO @v_parameter


select @v_paralist = Left(@v_paralist, len(@v_paralist) -1)
select @v_paravaluelist = Left(@v_paravaluelist, len(@v_paravaluelist) -1)

CLOSE table_cursor
DEALLOCATE table_cursor

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