SQL Basics

Core SQL fundamentals: SELECT, WHERE, JOIN, GROUP BY, and aggregates.

Progress: 0/10

Beginner � ~12 min

Q1. Which SQL clause is used to filter rows returned by a SELECT query?

Select one answer � 1 pt

HAVING ORDER BY WHERE GROUP BY

Q2. Which keyword returns only unique rows?

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ONLY SINGLE DISTINCT UNIQUE

Q3. What does COUNT(*) return?

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The number of tables in the database The number of rows returned The sum of all numeric columns The number of non-NULL values in a column

Q4. Which JOIN returns all rows from the left table and matching rows from the right table?

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CROSS JOIN LEFT JOIN RIGHT JOIN INNER JOIN

Q5. Which clause is used to sort results?

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ARRANGE SORT BY ORDER BY GROUP BY

Q6. Which statement adds a new row to a table?

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APPEND ADD ROW INSERT INTO UPDATE

Q7. What is the purpose of GROUP BY?

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To filter rows before SELECT To sort rows alphabetically To rename columns in results To group rows for aggregate calculations

Q8. Which clause filters groups after GROUP BY?

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HAVING WHERE LIMIT FROM

Q9. Which keyword limits the number of rows returned in MySQL?

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LIMIT TOP FETCH TAKE

Q10. What does an INNER JOIN return?

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Only matching rows from both tables All rows from both tables regardless of match No rows unless NULLs exist All rows from the left table

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