Reading EXPLAIN in PostgreSQL: ANALYZE, BUFFERS, Scan and Join Nodes, Statistics and pg_stat_statements
When you read a PostgreSQL plan, you first compare each node's estimated row count with the actual value from EXPLAIN ANALYZE; the planner's decisions rest on that estimate. Calculating cost by hand, BUFFERS on by default in 18, loops and fractional rows, nested loop, hash and merge joins, CREATE STATISTICS fixing an estimate off by 13 times, pg_stat_statements, GENERIC_PLAN and auto_explain catching an EF Core query's plan with its parameters.
14 Nov 2026
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17 min
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