In this chapter, PostgreSQL security is tackled from the authorization, authentication, and data encryption aspects; however, one also should protect the code against SQL injection and other known security issues, such as function cost, and the security barrier options. PostgreSQL provides several authentication methods, such as password and trust. Also, it provides security levels on all database objects including the database itself, schemas, tables, views, function, columns, and rows. Finally, one can also store sensitive data in the database in an encrypted format using pgcrypto extension. 

The next chapter will focus on the PostgreSQL system catalog and introduce several recipes to maintain the database. The recipes will be used to extract potential problems in the database, such as missing indexes, and introduce the solutions to tackle these problems.