
Explanation:
Option A:
| age | country |
|---|---|
| 80 | canada |
| NULL | canada |
| 90 | NULL |
Incorrect.
age = NULL fails age >= 75 (NULL comparisons return unknown/false in the WHERE clause).country = NULL fails country = 'canada'.Option B:
| age | country |
|---|---|
| 80 | NULL |
| 75 | NULL |
| 90 | NULL |
Incorrect.
country = NULL, which does not equal 'canada'.country = 'canada', so these rows should be filtered out entirely.Option C:
| id | age | country |
|---|---|---|
| 900 | 80 | canada |
| 901 | 75 | canada |
| 902 | 90 | canada |
Incorrect.
age and country. It does not include the id column.Option D:
| age | country |
|---|---|
| 80 | canada |
| 14 | canada |
| 90 | canada |
Incorrect.
age = 14 fails the condition age >= 75.Option E:
| age | country |
|---|---|
| 80 | canada |
| 75 | canada |
| 90 | canada |
Correct.
age >= 75 and country = 'canada'.age and country) are returned.The correct answer is E.
This question tests fundamental SQL concepts:
Mastering these basics is essential for the Databricks Certified Data Analyst - Associate exam, as many questions revolve around correct SQL filtering, projection, and understanding query output structure. Keep practicing similar queries by mentally applying the WHERE conditions to sample data!
Ultimate access to all questions.
A data analyst runs the following command:
SELECT age, country -
FROM my_table -
WHERE age >= 75 AND country = 'canada';
SELECT age, country -
FROM my_table -
WHERE age >= 75 AND country = 'canada';
Which of the following tables represents the output of the above command?
A
| age | country |
|---|---|
| 80 | canada |
| NULL | canada |
| 90 | NULL |
B
| age | country |
|---|---|
| 80 | NULL |
| 75 | NULL |
| 90 | NULL |
C
| id | age | country |
|---|---|---|
| 900 | 80 | canada |
| 901 | 75 | canada |
| 902 | 90 | canada |
D
| age | country |
|---|---|
| 80 | canada |
| 14 | canada |
| 90 | canada |
E
| age | country |
|---|---|
| 80 | canada |
| 75 | canada |
| 90 | canada |