Press "Enter" to skip to content

The Postgres Portal: Executor and Process Utility

Cary Huang digs into Postgres:

I wrote another blog to briefly explain the responsibility of each query processing stage. You can find it here. In this blog. There is one that focuses primarily on the planner module that you can find here. In this blog, we will focus on the executor part of the query processing, which is the entry point to “communicate” with other PostgreSQL internal modules to collect the correct data for the query.

In fact, executor may not be the best term to describe this stage. In the PostgreSQL source code, it is actually “packaged” in another object called “portal”. Often, and it has 2 potential paths to take, the “executor” path, or the “process utility” path. Very often, we just call this stage as “executor” rather than “portal”, because executor handles most of the DML query types that involve SELECT, INSERT, UPDATE, DELETE…etc and it has to process them according to the query plan created by the “planner” module.

Read on to learn more about the portal and its two component parts.