存储过程中变量为空应当怎么_Sql Server

存储过程中变量为空应当如何？

SET @sql_word= 'insert into '+@ResultTable +'
							select distinct EXITSTATION,11,exitdate,RECORDTYPE,vehicleclass,totaltoll
							from '+@BaseTable+' 
							where EXITSTATION = '+@Station+'
							GROUP BY exitdate,EXITSTATION,RECORDTYPE,vehicleclass,totaltoll
							order by EXITSTATION,exitdate,RECORDTYPE,vehicleclass,totaltoll'
			print(@sql_word)				
			exec(@sql_word)

如果我的@Station 为空，这个代码便会报错，请问怎样表现才会让我@Station 变量为空时跳过这行？

------解决方案--------------------


if @Station <>''
begin
SET @sql_word= 'insert into '+@ResultTable +'
                            select distinct EXITSTATION,11,exitdate,RECORDTYPE,vehicleclass,totaltoll
                            from '+@BaseTable+' 
                            where EXITSTATION = '+@Station+'
                            GROUP BY exitdate,EXITSTATION,RECORDTYPE,vehicleclass,totaltoll
                            order by EXITSTATION,exitdate,RECORDTYPE,vehicleclass,totaltoll'
end

就这样改。再试试
------解决方案--------------------
try this,


SET @sql_word= 'insert into '+@ResultTable
             +' select distinct EXITSTATION,11,exitdate,RECORDTYPE,vehicleclass,totaltoll '
             +' from '+@BaseTable 
             +' where 1=1 '+case when @Station<>'' then ' and EXITSTATION='''+@Station+''' ' else '' end