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Hash joins 🔑
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From Excel to SQL
Everything about joins
Challenging SQL problems
SQL Learning Materials
GitHub
Home
From Excel to SQL
From Excel to SQL
From Excel to SQL
Getting Started
Getting Started
Setting the context 🤔
SQL syntax 📚
Main Concepts
Main Concepts
Gimme data 📁
Filtering 🚦
Ordering ⏬
Comments 📝
TOP and DISTINCT 🔝
Data types 🧱
Operators ➕
Conditionals 🔀
Date formatting 📆
Aggregations 📊
Pivot tables 🧮
Joins 🔗
Unions 🧬
Subqueries 🧩
Window functions 📈
Logical processing order 🎥
Style guide ✨
Advanced Concepts
Advanced Concepts
Advanced aggregations 🥇
Correlated subqueries 🌐
Recursive CTEs 🔁
Everything about joins
Everything about joins
Everything about joins
Syntax
Syntax
Join fundamentals 🧩
More fundamentals 📚
The "timestamp" join (ASOF) ⏱
The "filtering" joins (SEMI, ANTI) 🚦
The "glue" join (POSITIONAL) 📎
The "explosive" joins (LATERAL) 💥
SQL-92 (ANSI-SQL join syntax) 📝
Under the hood
Under the hood
Joins with an index 🔍
Does join order matter? 🤔
Loop joins 🔄
Hash joins 🔑
Merge joins 🔀
Range intersection joins 🎯
Challenging SQL problems
Challenging SQL problems
Challenging SQL problems
Problems
Problems
🟤 Bronze Tier
🟤 Bronze Tier
Temperature anomaly detection 🔍
Outstanding invoices 💱
Personalised customer emails 📨
Suspicious login activity 🤔
Combining dimensions 🔗
Customer churn 🔄
Fibonacci sequence 🔢
UK bank holidays 📅
⚪ Silver Tier
⚪ Silver Tier
Metric correlation 🔀
Funnel analytics ⏬
Bannable login activity ❌
Bus routes 🚌
Decoding datelist ints 🔓
Region precipitation ☔
Predicting values 🎱
Mandelbrot set 🌀
Customer sales running totals 📈
🟡 Gold Tier
🟡 Gold Tier
Loan repayment schedule 💰
Risk invasions 🛡️
Supply chain network 🚛
Encoding datelist ints 🔐
Travel plans 🚂
Solutions
Solutions
🟤 Bronze Tier
🟤 Bronze Tier
Temperature anomaly detection 🔍
Outstanding invoices 💱
Personalised customer emails 📨
Suspicious login activity 🤔
Combining dimensions 🔗
Customer churn 🔄
Fibonacci sequence 🔢
UK bank holidays 📅
⚪ Silver Tier
⚪ Silver Tier
Metric correlation 🔀
Funnel analytics ⏬
Bannable login activity ❌
Bus routes 🚌
Decoding datelist ints 🔓
Region precipitation ☔
Predicting values 🎱
Mandelbrot set 🌀
Customer sales running totals 📈
🟡 Gold Tier
🟡 Gold Tier
Loan repayment schedule 💰
Risk invasions 🛡️
Supply chain network 🚛
Encoding datelist ints 🔐
Travel plans 🚂
Questions by topic
Hash joins 🔑
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