Reading an EXPLAIN Plan
EXPLAIN shows the optimizer's chosen plan as a tree of operators (scans, joins, sorts, aggregates) executed leaves-first, each annotated with estimated cost and row count. Reading it means finding which node dominates total cost and whether the access paths match your expectations.
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EXPLAIN shows the optimizer's chosen plan as a tree of operators (scans, joins, sorts, aggregates) executed leaves-first, each annotated with estimated cost and row count. Reading it means finding which node dominates total cost and whether the access paths match your expectations.
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