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: “The community has removed this feature and introduced a new variable called transaction_timeout, which can be set per session.”

A block of code is set as follows:

CREATE OR REPLACE FUNCTION on_login_proc()
RETURNS event_trigger AS
$$
BEGIN
    INSERT INTO user_lo (w) VALUES (SESSION_USER);
    RAISE NOTICE 'You are welcome!';
END;
$$ LANGUAGE plpgsql;

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

test=# SHOW event_triggers;
 event_triggers

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

test=# CREATE TABLE t_data (
    id    int,
    data  text
);

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: “A new process called summarizer was added to PostgreSQL.”

Tips or important notes

Appear like this.