In this chapter, we will discuss some more advanced SQL features supported by PostgreSQL that were not covered in the previous chapters. Some query writing techniques will also be described.

In this chapter, we will cover the following topics:

• Common table expressions
• Window functions
• Advanced SQL techniques

The same sample database car_portal is used in the code examples here. It is recommended though to recreate the sample database in order to get the same results as shown in the code examples. The scripts to create the database and fill it with data (schema.sql and data.sql) can be found in the attached code bundle for this chapter. All the code examples of this chapter can be found in the examples.sql file.