SQL Update
6.What happens if you try to update a non-existent row (with incorrect condition)?
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A. An error occurs
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B. Table is locked
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C. No rows are affected
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D. Null values are added
No rows are affected
No rows are affected
7.How can you update values based on another table?
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A. JOIN + UPDATE
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B. INSERT
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C. DROP
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D. MERGE
JOIN + UPDATE
JOIN + UPDATE
8.Which SQL statement updates salaries by 10% for department_id = 5?
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A. UPDATE employees SET salary = salary * 1.1 WHERE department_id = 5;
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B. UPDATE SET salary * 1.1 WHERE department_id = 5 FROM employees;
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C. UPDATE salary FROM employees WHERE department_id = 5 * 1.1;
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D. ALTER employees salary 1.1 WHERE department = 5;
UPDATE employees SET salary = salary * 1.1 WHERE department_id = 5;
UPDATE employees SET salary = salary * 1.1 WHERE department_id = 5;
9.Which command helps track how many rows were updated?
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A. SELECT COUNT(*)
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B. SHOW AFFECTED
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C. System message or API like rowCount()
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D. DEBUG UPDATE
System message or API like rowCount()
System message or API like rowCount()