Automatic EXPLAIN Plan Collection: Stop Guessing Why Queries Are Slow

Automatic EXPLAIN Plan Collection: Stop Guessing Why Queries Are Slow If you have ever scrambled to run EXPLAIN during a production incident, you already know the fundamental problem: by the time y...

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Automatic EXPLAIN Plan Collection: Stop Guessing Why Queries Are Slow

Source: DEV Community

Automatic EXPLAIN Plan Collection: Stop Guessing Why Queries Are Slow If you have ever scrambled to run EXPLAIN during a production incident, you already know the fundamental problem: by the time you are debugging, you have no baseline to compare against. The plan you are looking at right now might be perfectly normal, or it might be radically different from what it was yesterday. Without historical plans, you are guessing. The Problem Most teams never run EXPLAIN until something is on fire. A query degrades gradually over weeks as a table grows from 2 million to 20 million rows, the planner's cost estimates shift, and execution time creeps from 50ms to 500ms. Nobody notices because the change is incremental — until one day it crosses a threshold and response times spike. The worse scenario is a sudden plan change. PostgreSQL runs ANALYZE, statistics shift slightly, and the planner switches from an index scan to a hash join. A query that ran in 5ms now takes 250ms. You know something g