Quartz 4

05-查询处理

1 min read

01 查询处理概述

DBMS的查询处理器

DBMS的查询处理器

SQL语句分类

SQL语句分类

DDL/DCL语句处理

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create table t1(
	col int, primary key
    col2 int
);

DML与查询语句处理

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02 查询编译

查询编译概览

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语法树和SQL是完全等价的

词法/语法分析

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逻辑查询优化

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物理查询优化

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03 查询执行算法

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索引扫描：先找key再找value

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还有hash桶

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04 查询执行模型

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物化模型

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只有在Hash join时需要在外面建Hash表时需要物化

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05 查看执行计划

Graph View