Like most other relational database products, PostgreSQL supports aggregate functions. An aggregate function computes

Thus far, our queries have only accessed one table at a time. Queries can access multiple tables at once, or access the same table in such a way that multiple rows of the table

The INSERT statement is used to populate a table with rows:

The first test to see whether you can access the database server is to try to create a database. A running PostgreSQL server can manage many

Transactions are a fundamental concept of all database systems. The essential point of a transaction is that it bundles multiple steps into a single

You can create a new table by specifying the table name, along with all column names and their types:

PostgreSQL is a relational database management system (RDBMS). That means it is

Recall the weather and cities tables from Chapter 2. Consider the following problem: You want to make sure that

Before you can use PostgreSQL you need to install it, of course. It is possible that PostgreSQL is already

Refer back to the queries in Section 2.6. Suppose the combined listing