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: "Many experienced PostgreSQL DBAs will prefer to execute their own VACUUM
 commands."
A block of code is set as follows:
autovacuum = on track_counts = on
When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:
$ ln -sf autovacuum.conf.night autovacuum.conf $ pg_ctl reload
Any command-line input or output is written as follows:
VACUUM (DISABLE_PAGE_SKIPPING);
Tips or important notes
Appear like this.