prompt 中一些特殊的转义字符串
| Option | Description | 
|---|---|
\c | 
A counter that increments for each statement you issue | 
\D | 
The full current date | 
\d | 
The default database | 
\h | 
The server host | 
\l | 
The current delimiter (new in 5.1.12) | 
\m | 
Minutes of the current time | 
\n | 
A newline character | 
\O | 
The current month in three-letter format (Jan, Feb, …) | 
\o | 
The current month in numeric format | 
\P | 
am/pm | 
\p | 
The current TCP/IP port or socket file | 
\R | 
The current time, in 24-hour military time (0–23) | 
\r | 
The current time, standard 12-hour time (1–12) | 
\S | 
Semicolon | 
\s | 
Seconds of the current time | 
\t | 
A tab character | 
\U | 
 Your full   | 
\u | 
Your user name | 
\v | 
The server version | 
\w | 
The current day of the week in three-letter format (Mon, Tue, …) | 
\Y | 
The current year, four digits | 
\y | 
The current year, two digits | 
\_ | 
A space | 
\  | 
A space (a space follows the backslash) | 
\' | 
Single quote | 
\" | 
Double quote | 
\\ | 
A literal “\” backslash character | 
\ | 
 
  |