Postgres Build 2021

Aggregates are one of the most commonly used features of PostgreSQL, but many people don’t understand how they work. This talk will provide a brief overview of how aggregates work in PostgreSQL through pictures including:
-Transition, final and combine functions
-Parallel aggregation
-Aggregate de-duplication and optimization

Then we will go over how you can use this knowledge to construct custom aggregates for use in your applications, with examples of how to design custom aggregates to fill specific needs and work efficiently.