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1.Talk to a Table

Say “Hello” to the Table Say “Hello” to the Table - Repaired Quiz: Say “Hello” to the Table Challenge: Say “Hello” to the Table Solution: Say “Hello” to the Table Pick the Columns You Want Quiz: Pick the Columns You Want Challenge: Pick the Columns You Want Solution: Pick the Columns You Want Find the Rows That Matter Quiz: Find the Rows That Matter Problem: Find the Rows That Matter Solution: Find the Rows That Matter Use Comparisons and Logic Quiz: Use Comparisons and Logic Problem: Use Comparisons and Logic Solution: Use Comparisons and Logic Sort the Answers Quiz: Sort the Answers Problem: Sort the Answers Solution: Sort the Answers Problem: Help a Pet Lover Solution: Help a Pet Lover

2.Ask Better Questions

Do Math with Your Data Quiz: Do Math with Your Data Problem: Do Math with Your Data Solution: Do Math with Your Data Group Things Together Quiz: Group Things Together Problem: Group Things Together Solution: Group Things Together Only Keep Interesting Groups Quiz: Only Keep Interesting Groups Problem: Only Keep Interesting Groups Solution: Only Keep Interesting Groups Ask Questions About Questions Quiz: Ask Questions About Questions Problem: Ask Questions About Questions Solution: Ask Questions About Questions Project: Find the Top Performers

3.Create Your Own World

Create a Table Quiz: Create a Table Challenge: Create a Table Solution: Create a Table Add Some Data Quiz: Add Some Data Problem: Add Some Data Solution: Add Some Data Fix Mistakes Quiz: Fix Mistakes Problem: Fix Mistakes Solution: Fix Mistakes Design Better Tables Quiz: Design Better Tables Problem: Design Better Tables Solution: Design Better Tables Project: Build a Student Tracker

4.Connect the Dots

Meet the JOIN Family Quiz: Meet the Join Family Problem: Meet the JOIN Family Solution: Meet the JOIN Family Connect Two Tables Quiz: Connect Two Tables Problem: Connect Two Tables Solution: Connect Two Tables Go Multi-Level Quiz: Go Multi-Level Problem: Go Multi-Level Solution: Go Multi-Level Build a Mini Dashboard Problem: Build a Mini Dashboard Solution: Build a Mini Dashboard Project: Build a Mini Dashboard Project: Library Tracker Problem: Compute Student CGPA Solution: Compute Student CGPA Final Project: Build a Game Leaderboard

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Solution: Connect Two Tables

Solution: Connect Two Tables

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Query

SELECT s.id, s.name, g.score AS math_grade
FROM students s
LEFT JOIN grades g 
  ON s.id = g.student_id AND g.subject = 'Math';

Explanation

This query shows each student along with their Math grade (if available). ...