203 Articles tagged “PostgreSQL”

PostgreSQL connection strings embedded in your application can take two different forms: the key-value notation or the postgresql:// URI scheme. When it comes to using psql though, another form of connection string is introduced, with command line options -h -p -U and environment variable support.

In this short article you will learn that you can use either of the three different forms in psql and thus easily copy & paste you application connection string right at the console to test it!



I did it again! Today I am releasing the new edition of my book, with a new title: “The Art of PostgreSQL”. I’m very happy (and quite excited) to declare my book as Generally Available!

The Art of PostgreSQL is the new edition of my previous release, Mastering PostgreSQL in Application Development. It contains mostly fixes to the old content, a new title, and a new book design (PDF and paperback). Content wise, The Art of PostgreSQL also comes with a new whole chapter about PostgreSQL Extensions.

The new chapter covers extensions such as hstore, pg_trgm, intarray, earthdistance, ip4r, and hll or HyperLogLog, one of the all times favorite extensions of Craig Kerstiens… who made himself available to answer my questions and share his view of PostgreSQL Extensions in an interview!


An SQL Injection is a security breach, one made famous by the Exploits of a Mom xkcd comic episode in which we read about little Bobby Tables:

PostgreSQL implements a protocol level facility to send the static SQL query text separately from its dynamic arguments. An SQL injection happens when the database server is mistakenly led to consider a dynamic argument of a query as part of the query text. Sending those parts as separate entities over the protocol means that SQL injection is no longer possible.


We have loaded Open Street Map points of interests in the article The Most Popular Pub Names — which compares PostgreSQL with MongoDB for simple geographical queries, and is part of our PostgreSQL Extensions article series. In today’s article, look at how to geolocalize an IP address and locate the nearest pub, all within a single SQL query!

For that, we are going to use the awesome ip4r extension from RhodiumToad.


PostgreSQL is a relational database management system. It’s even the world’s most advanced open source one of them. As such, as its core, Postgres solves concurrent access to a set of data and maintains consistency while allowing concurrent operations.

In the PostgreSQL Concurrency series of articles here we did see several aspects of how to handle concurrent use cases of your application design with PostgreSQL. The main thing to remember is that a Database Management System first task is to handle concurrency access to the data for you.

Dimitri Fontaine

PostgreSQL Major Contributor

Open Source Software Engineer

France