mysql 的 help 命令：每个命令，都有相应的反斜杠（）加一个字母或字符的简写

mysql> help

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   http://dev.mysql.com/
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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.
connect   (
) Reconnect to the server. Optional arguments are db and host.
delimiter (d) Set statement delimiter.
edit      (e) Edit command with $EDITOR.
ego       (G) Send command to mysql server, display result vertically.
exit      (q) Exit mysql. Same as quit.
go        (g) Send command to mysql server.
help      (h) Display this help.
nopager   (
) Disable pager, print to stdout.
notee     (	) Don't write into outfile.
pager     (P) Set PAGER [to_pager]. Print the query results via PAGER.
print     (p) Print current command.
prompt    (R) Change your mysql prompt.
quit      (q) Quit mysql.
rehash    (#) Rebuild completion hash.
source    (.) Execute an SQL script file. Takes a file name as an argument.
status    (s) Get status information from the server.
system    (!) Execute a system shell command.
tee       (T) Set outfile [to_outfile]. Append everything into given outfile.
use       (u) Use another database. Takes database name as argument.
charset   (C) Switch to another charset. Might be needed for processing binlog with multi-byte charsets.
warnings  (W) Show warnings after every statement.
nowarning (w) Don't show warnings after every statement.
resetconnection(x) Clean session context.

For server side help, type 'help contents'

• 说明：

1. 每个命令，都有相应的反斜杠（）加一个字母或字符的简写；