while 条件
begin
----你的逻辑

end
或用游标 都可以

declare @col1 varchar(32),@col2 varchar(32)
declare v_cursor cursor for 
SELECT col1,col2 FROM tb 
open v_cursor
FETCH NEXT FROM v_cursor into @col1,@col2
while @@FETCH_STATUS = 0
begin
----你的逻辑
FETCH NEXT FROM v_cursor into @col1,@col2
end
CLOSE v_cursor
DEALLOCATE v_cursor