登录MySQL客户端后如何查看use、exit等内置命令？

要查看use、exit、clear、delimiter这类MySQL客户端内置交互命令，有两种实用方式：

1. 查看全部内置命令清单 #

在MySQL客户端提示符下输入以下任意命令并回车，就能获取完整的内置命令列表及简要说明：

help

也可以用缩写形式：

\?

\h

执行后会输出类似如下的内容（截取部分示例）：

List of all MySQL commands:
Note that all text commands must be first on line and end with ';'
? (?) Synonym for `help'.
clear (\c) Clear the current input statement.
delimiter (\d) Set statement delimiter.
exit (\q) Exit MySQL. Same as quit.
use (\u) Use another database. Takes database name as argument.
...

2. 查看单个命令的详细用法 #

如果想了解某一特定命令的具体使用方式，比如delimiter，可以在命令后跟上目标命令名称：

help delimiter

或者缩写形式：

\h delimiter

执行后会输出该命令的详细说明，例如：

Name: 'delimiter'
Description:
Set statement delimiter.

Syntax:
delimiter new_delimiter

new_delimiter is the new statement delimiter. It can consist of one or more characters.
The delimiter is set to ';' by default. Note that if you want to use a delimiter
that contains whitespace, you need to quote it.

内容的提问来源于stack exchange，提问作者Super Kai - Kazuya Ito