22.4 Summary

Adding your own functions, operators, and data types to PostgreSQL is an easy task because PostgreSQL provides simple and powerful interfaces for interacting with the database.

PostgreSQL provides a software package for working with substring indexes. This package is based on triggers and C functions. With the help of substring indexes, it is possible to speed up queries that do not look for entire strings.

With fuzzy input parameters, PostgreSQL offers a variety of possibilities. All functions you can use for fuzzy matching are available in a package that can be found in the contributed section of PostgreSQL's source code.