Below link is a good source for learning cursors in sql
http://www.cnblogs.com/moss_tan_jun/archive/2011/11/26/2263988.html
And I already made a little script for example.
The function of this script is, to check id & dcid for all students,
Then they 2 are not equal then change make this id to dcid's value.
And delete this cursor to free space in RAM.
Please make a cursor by yourself!
DECLARE
test_cursor CURSOR
FOR
select id,DCID FROM STUDENTS where dcid!=id
OPEN test_cursor
DECLARE @ID NVARCHAR(10)
DECLARE @DCID NVARCHAR(10)
FETCH NEXT FROM test_cursor INTO @ID,@DCID
while @@fetch_status=0
begin
print @id
print @dcid
update students set id=@dcid
where dcid=@dcid
fetch next from test_cursor into @id,@dcid
end
close test_cursor
deallocate test_cursor
Feel free to let me know if you have any question about this.
FYI, forum is a good source for learning everything about PC/MAC.
Here is a link, you can login with WeChat QR code.
http://www.csdn.net/
