postmodern-intro
Postmodern is a Common Lisp library for interacting with PostgreSQL databases.
Postmodern is a Common Lisp library for interacting with PostgreSQL databases.
Postmodern has very good documentation, but I always like to have examples. This is intended to be an introduction to the library for beginners using examples. This is not intended to be an sql tutorial, a lisp tutorial or a postgresql tutorial or a replacement for the postmodern s-sql manual.
Database Tables Used in Examples
Database Tables Used in Examples
I'm generally going to use a database with three tables - countries, regions and test for the examples below. The tables can be most simply described by looking at the following create-table queries:
(query (:create-table countries
((id :type int4 :primary-key t)
(name :type varchar :default "")
(region-id :type int4 :default 0)
(latitude :type numeric :default 0)
(longitude :type numeric :default 0)
(iso :type bpchar :default "")
(currency :type varchar :default "")
(text :type text :default "")
(:foreign-key (region-id) (regions id)))))
(query (:create-table regions ((id :type int4 :primary-key t)
(name :type varchar :default ""))))
(query (:create-table test
((id :type int4 :primary-key t)
(date :type timestamptz)(number-test :type numeric :default 0)
(money :type money :default 0)
(text :type text :default ""))))