让我们了解 MySQL 客户端-服务器端帮助 -
mysql> help search_string如果为上述“help”命令提供了参数，mysql将使用它作为搜索字符串来访问MySQL参考手册内容中的服务器端帮助。该命令的正确操作需要使用帮助主题信息初始化mysql数据库中的帮助表。
如果搜索字符串没有匹配，则搜索操作失败。让我们举个例子来理解这一点 -
mysql> help me输出
Nothing found
Please try to run 'help contents' for a list of all accessible topics我们可以使用帮助内容命令来查看帮助类别的列表。让我们举个例子来理解这一点 -
mysql> help contents输出
You asked for help about help category: "Contents"
For more information, type 'help <item>', where <item> is one of the
following categories:
Account Management
Administration
Data Definition
Data Manipulation
Data Types
Functions
Functions and Modifiers for Use with GROUP BY
Geographic Features
Language Structure
Plugins
Storage Engines
Stored Routines
Table Maintenance
Transactions
Triggers如果搜索字符串匹配多个项目，那么 mysql 将显示匹配主题的列表。让我们举个例子来理解这一点 -
mysql > help logs输出
Many help items for your request exist.
To make a more specific request, please type 'help <item>',
where <item> is one of the following topics:
SHOW
SHOW BINARY LOGS
SHOW ENGINE
SHOW LOGS
