sqlserver游标使用，遍历结果集，每行处理

---1.声明游标
declare    userInfo_cursor   cursor  scroll
for   select	 [id],[id_card]   from     [test2].[dbo].[db_user]

--2.打开游标
open userInfo_cursor

--3.声明游标提取数据所要存放的变量
declare @id varchar(100) ,@idcard varchar(100);
-- declare  @s_id   varchar(100);

--4.定位游标到哪一行
fetch First from userInfo_cursor into @id,@idcard  --into的变量数量必须与游标查询结果集的列数相同
while @@fetch_status=0  --提取成功，进行下一条数据的提取操作 
 begin
		-- if @OrderId=122182
		--	 begin
		--	 Update bigorder Set UserId='123' Where Current of  orderNum_03_cursor  --修改当前行
		--	 end
	  update   [Users]  set  [IdCard]=@idcard   where  RTRIM(  LTRIM([id]))=@id
	   print       @id+'  '+@idcard

	  -- select  @s_id= [id]  from  [Users]  where  RTRIM(  LTRIM([id]))=@id
      -- print    's_id='+@s_id+'   '+   @id+'  '+@idcard 
	  

   fetch next from userInfo_cursor into @id ,@idcard  --移动游标到下一行
 end  
 close           userInfo_cursor   --关闭游标
 deallocate   userInfo_cursor   --释放游标

参考博文：
Transact-SQL 游标
https://learn.microsoft.com/zh-cn/sql/t-sql/language-elements/declare-cursor-transact-sql?view=sql-server-ver16
https://learn.microsoft.com/zh-cn/sql/relational-databases/cursors?view=sql-server-ver16
https://learn.microsoft.com/zh-cn/sql/t-sql/functions/cursor-rows-transact-sql?view=sql-server-ver16

https://www.cnblogs.com/knowledgesea/p/3699851.html
http://www.manongjc.com/detail/18-gxrilqbqmdaruvy.html

滚动和提取行
https://learn.microsoft.com/zh-cn/sql/relational-databases/native-client-odbc-cursors/scrolling-and-fetching-rows?view=sql-server-ver16