what is index

Index data structure

Advantages and Disadvantages of Indexing

Index classification

Index test

explain

Explain ID introduction

Explain's select_type introduction

Explain type introduction -1

Explain type introduction -2

Explain type introduction -3

Explain's possible keys and key introduction

Explain's ref introduction

Introduction to Explain

Explainvalueextra introduction

Index invalidation -1

Index failure -2

Index failure -3

Sorting optimization

Optimization case

Joint table query optimization

Group query optimization

Slow query log