PostgreSQL

Basic Usage

Connect to db

In text retrieval, full-text search refers to techniques for searching
a single computer-stored document or a collection in a full text database.
Full-text search is distinguished from searches based on metadata or on
parts of the original texts represented in databases. - Wikipedia

A Document is the unit of searching in a full text search system;
for example, a magazine article or email message. -

Pass the tsvector into the function using which says “return true if the tsvector matches the tsquery”.

eg.

Aggregate Expressions

concatenates

Reference

http://blog.lostpropertyhq.com/postgres-full-text-search-is-good-enough/#1