Mi store Procedure no funciona

[Andres95]

Que tal asi??

Código:

CREATE PROC dbo.sp_FSopTec_generar_codsol
       @codsol varchar(10)OUTPUT 
AS 
Declare @maxsol as int


Select @MaxSol = 0

SELECT @maxsol=MAX(CAST(SUBSTRING(fst_cod,2,4) AS integer)) 
FROM   FSopTec (nolock)

Select @MaxSol = isnull(@Maxsol, 0) + 1

Select @codsol = right('0000' + convert(varchar(10),@maxsol) + '-', 5) + convert(varchar(20),year(getdate()),100)

Select @codsol = isnull(@codsol, '')
RETURN
GO