以一道题来做引子 牛客，SQL30 计算总和 OrderItems表代表订单信息，包括字段：订单号order_num和item_price商品售出价格、quantity商品数量。
I usually open many files in tabs with vim -p. Is it possible to check if any of the files was changed outside of Vim since e开发者_运维百科diting started?Add these lines to your .vimrc:
加载中,请稍侯......