Calling Dynamic Variable within a select

Question

Hi
Trying to build up a dynamic proc and can't see to figure out why I can re use variable  If I specify within the select what the code is then its fine but when I add in the variable doesn't workany help would be great !
create table basetable (id int, code varchar(15))
insert into basetable values (1,'SAP'),(2,'REG'),(3,'NRI')
create table Transactiontable (id int identity(1,1), baseid int, Product varchar(15))
insert into Transactiontable values (1,'AAAA'),(1,'BBBB'),(1,'CCCC'),(1,'DDDD'),(1,'unknown'),(2,'AAAA')
DECLARE @SQL NVARCHAR(max),@Cols NVARCHAR(max),@Cols2 NVARCHAR(max);
SELECT * FROM basetable
SELECT * FROM Transactiontable
DECLARE @SQL NVARCHAR(max),@Cols NVARCHAR(max),@Cols2 NVARCHAR(max), @Code NVARCHAR (3) ;
SET @CODE = 'REG'
;WITH mycte0
     AS (SELECT ROW_NUMBER()
                  OVER(
                    partition BY baseid
                    ORDER BY id) rn
         FROM   transactiontable ),
     mycte
     AS (SELECT DISTINCT rn
         FROM   mycte0)
SELECT @Cols = STUFF((SELECT ', ' + QUOTENAME(rn)
                      FROM   mycte
                      ORDER  BY rn
                      FOR XML PATH('')),
                     1,
                     2,
                     ,@Cols2 = STUFF((SELECT ', ' + QUOTENAME(rn) +' as [Product'+ cast(rn as varchar(5)) +']'
                      FROM   mycte
                      ORDER  BY rn
                      FOR XML PATH('')),
                     1,
                     2,
SET @SQL = 'select code,'+  @Cols2+' from (select b.code, t.Product, row_number() over(partition by t.baseid order by t.id) rn
from transactiontable t inner join basetable b on b.id=t.baseid where code = '+ @Code + ' --- ''REG''
) src PIVOT (max(Product) For rn In ('
           + @Cols + ')) pvt'
EXEC (@SQL)
DROP TABLE transactiontabledrop ;
DROP TABLE  basetable;

Answer 1

but when I add in the variable doesn't workany help would be great !
DECLARE @SQL NVARCHAR(max),@Cols NVARCHAR(max),@Cols2
NVARCHAR(max);
SELECT * FROM basetable
SELECT * FROM Transactiontable
DECLARE @SQL NVARCHAR(max),@Cols NVARCHAR(max),@Cols2
NVARCHAR(max), @Code NVARCHAR (3) ;
Within a batch the declare variable name must be unique,you can not (or don't Need to) declare it twice, like here @SQL, @Cols, @Cols2...
In the second declaration part just declare @Code and remove the other; they already exists.
Olaf Helper
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