SQL Query Writing for Data Reports

1. Which function calculates the total sum of values in a numeric column?

TOTAL()

SUM()

ADD()

AGGREGATE()

2. Which wildcard character in a LIKE clause matches any single character?

%

_

*

?

3. What does the AVG() function calculate?

The total sum of all values

The arithmetic mean of numeric values

The middle value in a dataset

The most frequently occurring value

Submit

5. Which join type returns all rows from both tables, matching where possible?

INNER JOIN

LEFT JOIN

FULL OUTER JOIN

CROSS JOIN

Submit

7. Which clause restricts aggregated results to groups meeting specific conditions?

WHERE

FILTER

HAVING

LIMIT

8. What is the correct syntax for a basic SELECT query structure?

SELECT FROM WHERE GROUP BY ORDER BY

SELECT ... FROM ... WHERE ... GROUP BY ... HAVING ... ORDER BY

FROM SELECT WHERE ORDER BY GROUP BY

SELECT WHERE FROM GROUP BY HAVING

Submit

10. A CROSS JOIN produces how many result rows?

Product of row counts from both tables

Same as the larger table

Only matching rows

Same as the smaller table

11. Which SQL clause is used to filter rows after aggregation in a GROUP BY query?

WHERE

HAVING

FILTER

ON

Submit

13. What does the WHERE clause filter in a SQL query?

Rows before aggregation

Columns in the result set

Aggregated group results

Join conditions only

Submit

15. Which aggregate function returns the middle value of a dataset?

AVG()

MEDIAN()

PERCENTILE()

MID()

16. What is the primary purpose of the DISTINCT keyword in a SELECT statement?

Remove duplicate rows from results

Sort results alphabetically

Filter NULL values only

Group rows by column value

Submit

18. Which statement is true about INNER JOIN?

It includes all unmatched rows from both tables

It returns only rows with matching values in both tables

It prioritizes the left table over the right

It removes duplicate rows automatically

Submit

20. What does a LEFT JOIN return?

Only matching rows from both tables

All rows from the left table plus matches from the right

All rows from the right table plus matches from the left

Rows where left table values are NULL

Data Analyst Writing a Query to Extract Report Data Quiz

1. Which function calculates the total sum of values in a numeric column?

2.

What first name or nickname would you like us to use?

2. Which wildcard character in a LIKE clause matches any single character?

3. What does the AVG() function calculate?

4. In data extraction queries, the ______ clause limits the number of rows returned.

5. Which join type returns all rows from both tables, matching where possible?

6. The ______ function returns the highest value in a column.

7. Which clause restricts aggregated results to groups meeting specific conditions?

8. What is the correct syntax for a basic SELECT query structure?

9. The ______ keyword in SQL is used to combine results from multiple SELECT queries.

10. A CROSS JOIN produces how many result rows?

11. Which SQL clause is used to filter rows after aggregation in a GROUP BY query?

12. The SQL ______ operator is used to find values matching a pattern with wildcards.

13. What does the WHERE clause filter in a SQL query?

14. In a GROUP BY query, unaggregated columns must be included in the ______ clause.

15. Which aggregate function returns the middle value of a dataset?

16. What is the primary purpose of the DISTINCT keyword in a SELECT statement?

17. The SQL ______ keyword is used to sort query results in ascending or descending order.

18. Which statement is true about INNER JOIN?

19. In SQL, the ______ function is used to count non-NULL values in a column.

20. What does a LEFT JOIN return?