Explaining the Postgres Query Optimizer

by Bruce Momjian
The optimizer is the "brain" of the database, interpreting SQL queries and determining the fastest method of execution.
This talk uses the EXPLAIN command to show how the optimizer interprets queries and determines optimal execution. Examples include scan methods, index selection, join types, and how ANALYZE statistics influence their selection. The talk will assist developers and administrators in understanding how Postgres optimally executes their queries and what steps they can take to understand and perhaps improve its behavior.