[songhongkang MySQL database] [advanced chapter] [06] logical architecture of MySQL

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Continuous learning & Ongoing update …

Learning attitude ： Keep breaking away

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Logical architecture analysis

The server handles client requests

Connectors

first floor adjoining course

The second floor Service layer

PS： Query cache component usage SQL Sentence as key, Query results as value; The hit rate is very low , Very chicken ribs .

The third level Engine layer

mysql> show engines;

Storage layer

Summary

SQL Execute the process

MySQL Medium SQL Execute the process

1. The query cache

The recommendation ：（ Be careful ：MySQL8.0 Query caching is not allowed ）

Do not use query caching ：

2. Parser

3. Optimizer

4. actuator

summary

• The query cache
• Parser ： Lexical analysis 、 Syntax analysis 、 Semantic check ——> The parse tree
• Optimizer ： Logic optimization 、 Physical optimization ——> Implementation plan
• actuator ： Call the storage engine API perform

MySQL8.0 in SQL Execution principle

1. confirm profiling Open or not

2. Perform the same many times SQL Inquire about

3. perform profiles

4. see profile

MySQL5.7 in SQL Execution principle

SQL Grammatical order

Database buffer pool

Buffer pool vs The query cache

How the buffer pool reads data

see / Set the size of the cache pool

Multiple Buffer cache example

Extended question

Reference resources

Song Hongkang in Silicon Valley : MySQL database （ Entry to advanced , Rookie to Daniel ）.

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The end of this paper , Thank you for your attention and support ！

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