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create     proc   test1
 
  @sale_name   varchar(50),

  @quyu   varchar(50),

  @subxingzhi_name   varchar(50),

  @developer_name   varchar(50),
  @room_type   int,
  @chaoxiang   varchar(50),
  @area   float,
  @price   float,

  @sql   varchar(8000)   output

as
set   @sql= 'select   distinct   *   from   sale  
a,householdmodel   b,developers   c   ,subxingzhi   d  
where   a.sale_id=b.sale_id   and   a.developer_id=c.developer_id   and   a.subxingzhi_id=d.subxingzhi_id '  

  if   @sale_name <> '1 '
begin
set   @sql=@sql+ '   and   a.sale_name= ' ' '+@sale_name+ ' ' ' '
end


if   @quyu <> '1 '
begin
set   @sql=@sql+ '   and   a.quyu= ' ' '+@quyu+ ' ' ' '
end


if   @subxingzhi_name <> '1 '
begin
set   @sql=@sql+ '   and   d.subxingzhi_name= ' ' '+@subxingzhi_name+ ' ' ' '
end


if   @developer_name <> '1 '
begin
set   @sql=@sql+ '   and     c.developer_name= ' ' '+@developer_name+ ' ' ' '
end


if   @room_type <> '1 '
begin
set   @sql=@sql+ '   and     b.room_type= '+ '@room_type '
end


if   @chaoxiang <> '1 '
begin
set   @sql=@sql+ '   and     b.chaoxiang= ' ' '+@chaoxiang+ ' ' ' '
end


if   @area <> '1 '
begin
set   @sql=@sql+ '   and     a.area= '+ '@area '

end


if   @price <> '1 '
begin
set   @sql=@sql+ '   and   a.price= '+ '@price '
end


print   @sql
exec   (@sql)


当我执行的时候提示:
exec   test1   '2 ', '2 ', '2 ', '2 ', '2 ', '2 ', '2 ', '2 ',2

提示错误：
select   distinct   *   from   sale  
a,householdmodel   b,developers   c   ,subxingzhi   d  
where   a.sale_id=b.sale_id   and   a.developer_id=c.developer_id   and   a.subxingzhi_id=d.subxingzhi_id   and   a.sale_name= '2 '   and   a.quyu= '2 '   and   d.subxingzhi_name= '2 '   and     c.developer_name= '2 '   and     b.room_type=@room_type   and     b.chaoxiang= '2 '   and     a.area=@area   and   a.price=@price
服务器:   消息   137，级别   15，状态   2，行   3
必须声明变量   '@room_type '。



------解决方案--------------------
修改

create proc test1

@sale_name varchar(50),

@quyu varchar(50),

@subxingzhi_name varchar(50),

@developer_name varchar(50),
@room_type int,
@chaoxiang varchar(50),
@area float,
@price float,

@sql varchar(8000) output

as