The following conventions are used in the synopsis of a command:
brackets ([ and ]) indicate
optional parts. Braces
({ and }) and vertical lines
(|) indicate that you must choose one
alternative. Dots (...) mean that the preceding element
can be repeated. All other symbols, including parentheses, should be
taken literally.
Where it enhances the clarity, SQL commands are preceded by the
prompt =>, and shell commands are preceded by the
prompt $. Normally, prompts are not shown, though.
An administrator is generally a person who is in charge of installing and running the server. A user could be anyone who is using, or wants to use, any part of the PostgreSQL system. These terms should not be interpreted too narrowly; this book does not have fixed presumptions about system administration procedures.