- DBNAME
This variable holds the name of the database psql is currently connected to. This variable is set
whenever psql connects to a database, either when starting up or when instructed to connect during
program operation.
- ECHO
This variable controls what gets displayed on the screen when executing commands from a file. To display all
contents of a script file on the screen as it is parsed, set this variable to all. To display all
queries as they are sent to the backend process, set this variable to queries.
- ECHO_HIDDEN
This variable, when set to true, displays the queries used by slash commands from within
psql. Such queries will be displayed before they are sent to the backend. To show the queries for
slash commands without actually executing them, set ECHO_HIDDEN to noexec.
- ENCODING
This variable holds the database's multibyte encoding scheme. You must have compiled
PostgreSQL to support multibyte encoding; if you did not, this variable will contain SQL_ASCII.
- HISTCONTROL
This variable sets methods of controlling the psql history buffer. Set this variable
to ignorespace if you wish for the history to ignore all lines entered that were preceded by
spaces. Set it to ignoredups to ignore any entries that matched the previous line entered. To
ignore both lines beginning with spaces and lines that duplicate, use the value ignoreboth.
- HISTSIZE
This variable sets the length of the history buffer; the default length is 500 lines.
- HOST
This variable holds the hostname of the database server you are currently connected to. This value is set during
startup and whenever a database connection occurs.
- IGNOREEOF
This variable controls how psql handles EOF characters.
Normally, when psql receives an EOF character the application terminates. This character is
usually generated by pressing CTRL-D on the keyboard. Setting this option to any non-numeric value will inform
psql that you wish to have the EOF character ignored until it is repeated more than 10 times.
You may alternatively set this variable to a specific number; if you do so, psql will ignore that many
EOF characters before terminating.
- LASTOID
This variable contains the last object identifier (OID) set from an INSERT command, or
lo_import() function call.
- LO_TRANSACTION
This variable sets the action psql will take during large object operations. It may
be set to one of the following values:
- rollback
This causes any transaction you are currently working within to be rolled back if you attempt an operation on a
large object (or a large object import). For maximum efficiency, large object operations should usually be
placed within their own transactions; for this reason, LO_TRANSACTION defaults to rollback.
- commit
This causes psql to commit any transaction you were in before you issued a large object operation.
- nothing
This causes psql to execute the large object operation within the current transaction.
- ON_ERROR_STOP
This variable, when set (to any value), causes psql to terminate the processing of a
script that encounters an error (such as incorrect SQL syntax or misuse of a slash command), instead of continuing to
process it. By default, scripts that have encountered errors continue to be processed by psql.
- PORT
This variable holds the port number that you are currently connected to. This value
is set automatically both when you start the program and when you manually connect
to a database from the psql prompt.
- PROMPT1, PROMPT2, PROMPT3
These variables hold character strings that directly control the prompt's structure within psql.
Setting these will change the way each prompt is displayed within the program. See Chapter 6, for
information on how to set these variables.
- SINGLELINE
This variable, when set (to any value), causes SQL input to psql to be executed when a
newline is reached, without the need for a semi-colon or \g terminator. This mode can also be set by the
command line option -S.
- SINGLESTEP
This variable, when set (to any value), causes each statement to require confirmation before being executed.
- USER
This variable holds the PostgreSQL username you are connected to the database with.
