SQL query dynamic table name in FOR

Question

I have a table tbl1 which has a column tbl_names. This column contains the name of some other tables.
Now I want to write a query in th

Answer 1

You can use prepared statements

SET @a = (select tbl_names from tbl1);
SET @x := CONCAT('SELECT * FROM ', @a);
Prepare stmt FROM @x;
Execute stmt;
DEALLOCATE PREPARE stmt;

PREPARE Syntax

Cheers.

Answer 2

You'll need to use some dynamic SQL. Build up a SQL string with the query that you want to execute and then call exec(@sql)

Full example:

declare cur cursor for
select tbl_names from tbl1

declare @sql varchar(100), @tbl varchar(100)

open cur

fetch cur into @tbl

while @@FETCH_STATUS = 0 begin
    set @sql = 'select * from ' + @tbl
    exec(@sql)
    fetch cur into @tbl
end

close cur
deallocate cur

Answer 3

Just add a pseudonim to the subquery:

select * from (select tbl_names from tbl1) a;

Good luck )