The first two articles in this series demonstrated how PostgreSQL is a capable tool for ELT – taking raw input and transforming it into usable data for querying and analyzing. We used sample data from the Advent of Code 2023 to demonstrate some of the ELT techniques in PostgreSQL.
In the first article, we discussed functions and features of SQL in PostgreSQL that can be used together to transform and analyze data. In the second article, we introduced Common Table Expressions (CTE) as a method to build a transformation query one step at a time to improve readability and debugging.