Once you're logged into a Postgresql database, you can issue the \? command to see the list of available "slash" commands. For my own convenience, I'm listing these here. These are the commands available in the Postgresql 8.0.3 client.

First, I issue the call for help:

mydatabase=> \?

And here is the help:

General
  \c[onnect] [DBNAME|- [USER]]
                 connect to new database (currently "ddblog")
  \cd [DIR]      change the current working directory
  \copyright     show PostgreSQL usage and distribution terms
  \encoding [ENCODING]
                 show or set client encoding
  \h [NAME]      help on syntax of SQL commands, * for all commands
  \q             quit psql
  \set [NAME [VALUE]]
                 set internal variable, or list all if no parameters
  \timing        toggle timing of commands (currently off)
  \unset NAME    unset (delete) internal variable
  \! [COMMAND]   execute command in shell or start interactive shell

Query Buffer
  \e [FILE]      edit the query buffer (or file) with external editor
  \g [FILE]      send query buffer to server (and results to file or |pipe)
  \p             show the contents of the query buffer
  \r             reset (clear) the query buffer
  \s [FILE]      display history or save it to file
  \w FILE        write query buffer to file

Input/Output
  \echo [STRING] write string to standard output
  \i FILE        execute commands from file
  \o [FILE]      send all query results to file or |pipe
  \qecho [STRING]
                 write string to query output stream (see \o)

Informational
  \d [NAME]      describe table, index, sequence, or view
  \d{t|i|s|v|S} [PATTERN] (add "+" for more detail)
                 list tables/indexes/sequences/views/system tables
  \da [PATTERN]  list aggregate functions
  \db [PATTERN]  list tablespaces (add "+" for more detail)
  \dc [PATTERN]  list conversions
  \dC            list casts
  \dd [PATTERN]  show comment for object
  \dD [PATTERN]  list domains
  \df [PATTERN]  list functions (add "+" for more detail)
  \dg [PATTERN]  list groups
  \dn [PATTERN]  list schemas (add "+" for more detail)
  \do [NAME]     list operators
  \dl            list large objects, same as \lo_list
  \dp [PATTERN]  list table, view, and sequence access privileges
  \dT [PATTERN]  list data types (add "+" for more detail)
  \du [PATTERN]  list users
  \l             list all databases (add "+" for more detail)
  \z [PATTERN]   list table, view, and sequence access privileges (same as \dp)

Formatting
  \a             toggle between unaligned and aligned output mode
  \C [STRING]    set table title, or unset if none
  \f [STRING]    show or set field separator for unaligned query output
  \H             toggle HTML output mode (currently off)
  \pset NAME [VALUE]
                 set table output option
                 (NAME := {format|border|expanded|fieldsep|footer|null|
                 recordsep|tuples_only|title|tableattr|pager})
  \t             show only rows (currently off)
  \T [STRING]    set HTML  tag attributes, or unset if none
  \x             toggle expanded output (currently off)

Copy, Large Object
  \copy ...      perform SQL COPY with data stream to the client host
  \lo_export LOBOID FILE
  \lo_import FILE [COMMENT]
  \lo_list
  \lo_unlink LOBOID    large object operations




  

 







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