postgresql

PostgreSQL Merge Join

Merge Join operation on two sorted inputs.

SELECT * FROM A JOIN B ON A.id = B.id (where both are sorted);

Merge Joins are very efficient if both inputs are already sorted on the join key (usually via an index). It zips the two streams together in a single pass.

Interactive Execution Plan

EXPLAIN Output

Run: EXPLAIN (ANALYZE, COSTS, VERBOSE, BUFFERS, FORMAT TEXT) your_query;

Enter SQL EXPLAIN output to visualizeSupports PostgreSQL EXPLAIN ANALYZE, MySQL EXPLAIN, and SQLite EXPLAIN QUERY PLAN formats