You came to the right place where you’ll learn some helpful commands that can help you out when you’re going to use PostgreSQL:

  • Let's say if we want to login as a different user (for example, guest1) to a database (food) that you have and want to go to, well you would write it like this: psql -U guest1 -d food -h localhost
  • If you want to exit out of the postgres client account, you would type out this command: \q
  • We can list all the databases by typing this out: \l or \list
  • To change into a particular databse, you can type this out: \c nba
  • In order to show a list of tables that is in your current database that you are in, you would type this out: \d or \dt
  • To describe the format of a particular table, this is the command to use: \d celtics
  • To describe in more detail the format of a particular table, you would be typing this out: \d+ celtics
  • To import sql commands from an sql file, you can type out: \i nba.sql
  • To delete a particular database, just type this out: DROP DATABASE nba
  • To show all the data in a table of your choice, just type this out: SELECT * FROM celtics

Source: http://www.postgresonline.com/downloads/special_feature/postgresql83_psql_cheatsheet.pdf