--- title: "Understanding Recursive SQL Queries" publication: "Postgres Weekly" issue: 347 published_at: "2020-03-18" canonical_url: "https://postgresweekly.com/issues/347" --- This week's Postgres news, views, and tools. #347 — March 18, 2020 [Read on the Web](https://postgresweekly.com/issues/347) Postgres Weekly [![\](https://res.cloudinary.com/cpress/image/upload/w_1280,e_sharpen:60/mgcubmrhlfofx0czovsu.jpg)](https://t.co/vLsE4PliwQ) [Understanding Recursive SQL Queries](https://t.co/vLsE4PliwQ) — Recursive common table expressions make it possible to work with dynamic graph or hierarchically structured data within Postgres. This is quite a nice, gentle introduction to the idea to allow you to move on to more advanced guides. Martin Heinz [Postgres is the World's Best Database: Here's Why](https://www.2ndquadrant.com/en/blog/postgresql-is-the-worlds-best-database/) — Yes! We need a little cheerleading this week, so why not cheerlead for Postgres? 😄 _“I intend to prove that by virtue of both design and implementation that PostgreSQL is objectively and measurably a better database than anything currently available..”_ All good arguments, too. Kirk Roybal [![\](https://copm.s3.amazonaws.com/23a52e43.png)](https://pgexperts.com/) [Your Data Is Your Business](https://pgexperts.com/) — PGX is a full-service database consultancy focused around PostgreSQL systems. Let us help you architect, build, troubleshoot and scale your PostgreSQL data systems on any platform or hosting environment. PostgreSQL Experts, Inc. sponsor [An Overview of Generated Columns](https://severalnines.com/database-blog/overview-generated-columns-postgresql) — It’s been several months since we enjoyed Rob Conery’s [dive into generaed columns](https://rob.conery.io/2019/10/24/virtual-computed-columns-in-postgresql-12/) but as one of Postgres 12’s headline new features, it’s worth getting up to speed if you haven’t already. The basic idea is that generated columns are special columns which contain data calculated on the fly from other data on the row, a little like spreadsheet functions. Brian Fehrle [Is Database Interoperability at Risk?](https://momjian.us/main/blogs/pgblog/2020.html#March_16_2020) — Bruce reflects on the current case going on between Oracle and Google over the latter’s alleged ‘copying’ of the Java API and whether it could affect database systems ‘copying’ each other’s SQL-related additions. Bruce Momjian [Spatial Tile Serving with Postgres Functions](https://info.crunchydata.com/blog/crunchy-spatial-tile-serving-with-postgresql-functions) — How to use functions along with PostGIS to generate dynamic map tiles on-the-fly with pg_tileserv and Crunchy Spatial. Paul Ramsey ▶[Azure Arc: Bring Hyperscale PostgreSQL to On-Premises and Multi-Cloud](https://www.youtube.com/watch?v=-Ijqf3LnL30) — Azure Arc is a still in-preview approach to deploying Azure services ‘anywhere’ across on-premise, edge, and multicloud environments. Umur Cubukcu and Nikhil Patel [Postgres's Date and Time Data Types Explained](https://nanmu.me/en/posts/2020/postgresql-date-and-time-data-types-explained/) Li Zhennan [How to Authenticate Postgres Users Against Amazon AWS Cognito](https://theplateisbad.blogspot.com/2020/03/authenticate-postgresql-users-against.html) — Cognito is a centralized user authentication system provided by AWS, but can it be used to authenticate Postgres users? Sort of. This post presents an initial attempt at solving the problem. ergo [💻 Live Webinar: How to Analyze Your Prometheus Data in SQL](https://tsdb.co/Analyzing-Prometheus-Webinar) — Learn how (and why) to use PostgreSQL to store & analyze monitoring metrics, write custom queries, visualize results in Grafana, and more. Timescale sponsor [pgagroal 0.5.0: A High Performance Postgres Connection Pool](https://agroal.github.io/pgagroal/) — Boasts significant performance [compared to the (unnamed) competition](https://agroal.github.io/pgagroal/performance.html). [0.5.0’s](https://agroal.github.io/pgagroal//release/announcement/2020/03/17/pgagroal-0.5.0.html) primary new feature is SCRAM-SHA-256 support. RedHat Inc. [check_pgbackrest 1.8: The pgBackRest Backup Monitor](https://pgstef.github.io/2020/03/18/check_pgbackrest_1_8.html) — So if you’re using [pgBackRest](https://pgbackrest.org/) for your Postgres backups, `check_pgbackrest` can plug into Nagios to keep an eye on things. Stefan Fercot [PAF (PostgreSQL Automatic Failover) 2.3.0 Released](https://github.com/ClusterLabs/PAF/releases) — A Pacemaker and Corosync based approach. Adds support for Postgres 12. ClusterLabs 🗓**Upcoming Events** **Note:** Due to the travel disruption caused by the ongoing COVID-19 outbreak, please check the status of events you are attending or wish to attend. We are checking each event we list prior to publication, but the situation can change quickly and it seems _very_ likely most in-person events will be postponed or cancelled. - [Swiss PGDay 2020](http://www.pgday.ch/2020/) (June 18-19 in Switzerland) — A two track conference (one in English, one in German) aimed at the entire Postgres community. - [Postgres Vision 2020](https://www.postgresvision.com/) (June 22-24 in Boston, MA) - [Postgres Ibiza 2020](https://pgibz.io/) (June 25-26 in Ibiza, Spain) — A two day conference on the sunny island of Ibiza in the Mediterranean. I recall this one getting some great trip reports last year! We are considering reworking this section to list _virtual_ events such as webinars, Twitch streams, and similar online get-togethers. If you are running any, please let us know! Curated by [Cooperpress](https://cooperpress.com/), [Peter Cooper](https://twitter.com/peterc), and [Craig Kerstiens](https://twitter.com/craigkerstiens). [Change your email address](https://postgresweekly.com/edit_subscription/*|UID|*) or[Stop getting this newsletter](https://postgresweekly.com/leave/*|UID|*) © Cooper Press Ltd · Fairfield Enterprise Centre, Louth, LN11 0LS, United Kingdom