Conventions used

There are a number of text conventions used throughout this book.

Code in text: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: “. You cannot run it inside a SELECT statement. Instead, you have to invoke CALL. The following listing shows the syntax of the CALL command.”

A block of code is set as follows:

test=# \h CALL
Command:    CALL
Description: invoke a procedure
Syntax:
CALL name ( [ argument ] [, ...] )
URL: https://www.postgresql.org/docs/15/sql-call.html

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

openssl req -x509 -in server.req -text
  -key server.key -out server.crt

Any command-line input or output is written as follows:

# - Connection Settings –
# listen_addresses = 'localhost'
# what IP address(es) to listen on;
# comma-separated list of addresses;
# defaults to 'localhost'; use '*' for all
# (change requires restart)

Bold: Indicates a new term, an important word, or words that you see onscreen. For instance, words in menus or dialog boxes appear in bold. Here is an example: “Select System info from the Administration panel.”

Tips or important notes

Appear like this.