Friday, July 28, 2017

7 ways to convince MySQL to use the right index



Sometimes MySQL gets it wrong. It doesn't use the right index. It happens that MySQL generates a query plan which is really bad (EXPLAIN says it's going to explore some 10,000,000 rows), when another plan (soon to show how was generated) says: "Sure, I can do that with 100 rows using a key".

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Finite-State Machines, Part 1: Modeling with Haskell Data Types

Stateful programs often become complex beasts as they grow. Program state incohesively spread across a bunch of variables, spuriously guar...