This chapter provides an overview of how to use SQL to perform simple operations. This tutorial is only intended to give you an introduction and is in no way a complete tutorial on SQL. Numerous books have been written on SQL, including
Understanding the New SQL
and
A Guide to the SQL Standard
. You should be aware that some PostgreSQL language features are extensions to the standard.
In the examples that follow, we assume that you have created a database named mydb, as described in the previous chapter, and have started psql.
Examples in this manual can also be found in the PostgreSQL source distribution in the directory src/tutorial/. To use those files, first change to that directory and run make:
$ cd
....
/src/tutorial
$ make
This creates the scripts and compiles the C files containing user-defined functions and types. (You must use GNU make for this — it may be named something different on your system, often gmake.) Then, to start the tutorial, do the following:
$ cd
....
/src/tutorial
$ psql -s mydb
...
mydb=> \i basics.sql
The \i command reads in commands from the specified file. The -s option puts you in single step mode which pauses before sending each statement to the server. The commands used in this section are in the file basics.sql.