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How do you read an EXPLAIN query plan?

Q: How do you read an EXPLAIN query plan?

**EXPLAIN** (and EXPLAIN ANALYZE for actual timings) shows how the database executes a query — join order, index usage, and operation types. Look for full table/sequential scans on big tables, costly sorts, and estimated vs actual row mismatches to guide indexing.

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Understand the problem

Explain EXPLAIN plans.

explain

Attempt it yourself

Sketch your approach before reading the solution — that's what interviews test.

Nudge consolestandby

Stuck? Beam a request up — the console returns a conceptual nudge that guides your logic without spoiling the implementation.

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EXPLAIN (and EXPLAIN ANALYZE for actual timings) shows how the database executes a query — join order, index usage, and operation types. Look for full table/sequential scans on big tables, costly sorts, and estimated vs actual row mismatches to guide indexing.

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SQLEXPLAIN Plan Playground

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