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SQL in Practice
From SELECT to the execution plan, all run by hand
중급 · Lessons 14 · Lab 5
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Curriculum
Selecting and Filtering
Select and Filter — Three-Valued Logic and the Order of Conditions
reading
Filtering and Expressions
lab
Quiz: Selecting and Filtering
quiz
Joins
Joins — Which Side Do You Keep
reading
Linking Scattered Data With Joins
lab
Quiz: Joins
quiz
Aggregates and Window Functions
Aggregates — What GROUP BY Actually Does
reading
Window Functions — Looking Sideways Without Folding
reading
Building Summaries With Aggregates
lab
Ranks and Trends With Window Functions
lab
Quiz: Aggregates and Window Functions
quiz
Performance and Execution Plans
EXPLAIN ANALYZE — What to Look At, and in What Order
reading
Dissecting an Execution Plan
lab
Quiz: Performance and Execution Plans
quiz
Reference docs
PostgreSQL — SQL 언어
PostgreSQL — 윈도 함수
PostgreSQL — EXPLAIN