Muhammad Ali explains explain plans:
In a previous post titled Exploring Postgres Performance: A Deep Dive into pg_stat_statements, we discussed the utility of pg_stat_statements as a tool for identifying resource-intensive queries in terms of memory, CPU, or I/O usage.
Now, let’s suppose you’ve pinpointed certain queries you’d like to investigate further. The EXPLAIN command is used to generate execution plans. It includes:
Read on to see what it includes, how you can generate an explain plan, and some of the optional settings.