SQLSERVER游标的使用

declare @user_name varchar(100)  
--定义一个游标  
declare user_cur cursor for select user_name from [T_CORE_USER] where Bh is null
--打开游标  
open user_cur  
while @@fetch_status=0  
begin 
--读取游标  
  fetch next from user_cur into @user_name

  begin  

			  if (select count(*) from T_smes_qyxx where qy_mc = @user_name )<=1			  

			  update  t1
			  set t1.BH = t2.QY_ID from [T_CORE_USER] t1,T_smes_qyxx t2
			  where t1.user_name    = @user_name and    t2.qy_mc    = @user_name
              and t1.Bh is null 

              print @user_name  


  end


end 
close user_cur  
--摧毁游标  
deallocate user_cur