Cost

Read the cost of a plan.

EXPLAIN shows the cost of each step. A low cost means a fast query.

EXPLAIN SELECT * FROM products;
-- cost=0.00..15.20 rows=150

Cost and row estimate.

All columns are selected from products.

Cost — details

Cost units are relative. Used for comparison, not absolute time.

You compare two versions of the same query with EXPLAIN and pick the one with lower cost; a smaller number means the plan is estimated to be cheaper.

See the cost of a query with EXPLAIN.

Show example solution

EXPLAIN SELECT * FROM products;

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