SQL: Dynamic Variable Names

Question

I am attempting to set variables whose names are dynamic in a stored procedure:

DECLARE @var01 varchar(50)  
DECLARE @var02 varchar(50) 
...
DECLARE @var30 v         


        

Answer 1

Since you are saying in comments that you are assigning the set of variables merely to insert the assigned values into a table, you could use an approach avoiding the variables altogether. You could insert all the values into a temporary table or table variable, providing them with numeric indices, then pivot the column of values and insert the resulting row into the target table. So, something like this:

DECLARE @values TABLE (Ind int IDENTITY(1,1), Value varchar(50));

INSERT INTO @values
SELECT ...
;

INSERT INTO TargetTable (Col1, Col2, ..., Col30)
SELECT [1], [2], ..., [30]
FROM @values
PIVOT (
  MAX(Value) FOR Ind IN ([1], [2], ..., [30])
) AS p
;

I even suspect there might also be a possibility to do everything in such a way as to avoid the cursor you are mentioning in comments.

Answer 2

You can also use stored procedure sp_executesql which allows passing parameters. Although I recommend to use additional table to store variables.

Answer 3

Well, it is not pretty, but you can do:

if @loopcntr = 1
    set var01 = 'somevalue'
else if @loopcntr = 2
    set var02 = 'whatever'
else if . . .

This should be sufficiently unpleasant that you might think of alternatives. Oh, here's a good one. Define a table variable and just add rows in for each value:

declare @vars table (
    id int identity(1, 1),
    loopcntr int,
    value varchar(255)
);

. . .
-- inside the loop
    insert into @vars(loopcntr, value)
        select @loopcntr, 'whatever';

When you want to get a variable, you can do:

declare @var varchar(255);
select @var = value from @vars where loopcntr = <the one I want>;