sqlserver 游标的使用

declare @temp_temp uniqueidentifier--临时变量
DECLARE aaa CURSOR for select Id from A
-------------------打开游标
open aaa
--先查询一次再循环，防止有多个游标时@@FETCH_STATUS=-1不能进入下个游标循环的情况
fetch next from aaa into @temp_temp
-------------------循环取数据
while @@FETCH_STATUS=0
begin
print @temp_temp
fetch next from aaa into @temp_temp

end
----------------------------------- 关闭游标
Close aaa
----------------------------------- 删除游标
Deallocate aaa

　　

游标的嵌套

declare @temp_temp uniqueidentifier--临时变量
DECLARE aaa CURSOR for select Id from A
-------------------打开游标
open aaa
--先查询一次再循环，防止有多个游标时@@FETCH_STATUS=-1不能进入下个游标循环的情况
fetch next from aaa into @temp_temp
-------------------循环取数据
while @@FETCH_STATUS=0
begin
print @temp_temp
	--===========================游标嵌套
	DECLARE bbb CURSOR for select Id from B
	-------------------打开游标
	open bbb
	--先查询一次再循环，防止有多个游标时@@FETCH_STATUS=-1不能进入下个游标循环的情况
	fetch next from bbb into @temp_temp
	-------------------循环取数据
	while @@FETCH_STATUS=0
	begin
	print @temp_temp
	fetch next from bbb into @temp_temp

	end
	----------------------------------- 关闭游标
	Close bbb
	----------------------------------- 删除游标
	Deallocate bbb
	--===========================游标嵌套
fetch next from aaa into @temp_temp

end
----------------------------------- 关闭游标
Close aaa
----------------------------------- 删除游标
Deallocate aaa