The prompts vsql issues can be customized to your preference.

The prompts vsql issues can be customized to your preference. The three variables PROMPT1, PROMPT2, and PROMPT3 contain strings and special escape sequences that describe the appearance of the prompt. Prompt 1 is the normal prompt that is issued when vsql requests a new command. Prompt 2 is issued when more input is expected during command input because the command was not terminated with a semicolon or a quote was not closed. Prompt 3 is issued when you run a SQL COPY command and you are expected to type in the row values on the terminal.

The value of the selected prompt variable is printed literally, except where a percent sign (%) is encountered. Depending on the next character, certain other text is substituted instead. Defined substitutions are:

The full host name (with domain name) of the database server, or [local] if the connection is over a socket, or [local:/dir/name], if the socket is not at the compiled in default location.
The host name of the database server, truncated at the first dot, or [local].
The port number at which the database server is listening.
The database session user name.
The name of the current database.
Like %/, but the output is ~ (tilde) if the database is your default database.
If the session user is a database superuser, then a #, otherwise a >. (The expansion of this value might change during a database session as the result of the command SET SESSION AUTHORIZATION.)
In prompt 1 normally =, but ^ if in single-line mode, and ! if the session is disconnected from the database (which can happen if \connect fails). In prompt 2 the sequence is replaced by -, *, a single quote, a double quote, or a dollar sign, depending on whether vsql expects more input because the command wasn't terminated yet, because you are inside a /* ... */ comment, or because you are inside a quoted or dollar-escaped string. In prompt 3 the sequence doesn't produce anything.
Transaction status: an empty string when not in a transaction block, or * when in a transaction block, or ! when in a failed transaction block, or ? when the transaction state is indeterminate (for example, because there is no connection).
The character with the indicated numeric code is substituted. If digits starts with 0x the rest of the characters are interpreted as hexadecimal; otherwise if the first digit is 0 the digits are interpreted as octal; otherwise the digits are read as a decimal number.
The value of the vsql variable name. See the section Variables for details.
The output of command, similar to ordinary "back- tick" substitution.
%[ ... %]
Prompts may contain terminal control characters which, for example, change the color, background, or style of the prompt text, or change the title of the terminal window. In order for the line editing features of Readline to work properly, these non-printing control characters must be designated as invisible by surrounding them with %[ and %]. Multiple pairs of these may occur within the prompt. The following example results in a boldfaced (1;) yellow-on-black (33;40) prompt on VT100-compatible, color-capable terminals:

testdb=> \set PROMPT1 '%[%033[1;33;40m%]%n@%/%R%#%[%033[0m%] '

To insert a percent sign into your prompt, write %%. The default prompts are '%/%R%# ' for prompts 1 and 2, and '>> ' for prompt 3.

Note: See the specification for terminal control sequences (applicable to gnome-terminal and xterm).