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Practical tutorials for the work we actually do. Pick one, read it in order, and apply it.

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SQL Testing and Debugging Advanced Clear filters 3 results
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Read EXPLAIN ANALYZE in 10 Minutes

Run one slow query with EXPLAIN ANALYZE and read it with a five-question checklist: rows touched, filtered rows, estimates, loops and sort spills. After this, you can find the slow node of a plan and check your fix.

5 min read
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Find Slow Queries With pg_stat_statements

Turn on pg_stat_statements in a Docker container and list the statements that cost the most in total. After this, you know which query to tune first, and you do not have to guess.

5 min read
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Find and Fix a Deadlock

Reproduce a deadlock between two money transfers, read the message, and fix it by locking rows in the same order. After this, you can turn a deadlock detected error into a plain wait.

5 min read