Share Latest Oct-2026 1Z0-171Test Practice Test Questions, Exam Dumps [Q41-Q60]

NO.41 What happens when a unique index is created on a table column?

NO.42 Which SQL function can be used to replace NULL values with a specified value?

NO.43 What does the following SQL statement do?
CREATE TABLE employees (
employee_id NUMBER PRIMARY KEY,
first_name VARCHAR2(50),
hire_date DATE NOT NULL
);

NO.44 What is required for the queries combined by a SET operator to work correctly?

NO.45 What will the following SQL query return?
SELECT TRUNC(15.678, 2) AS truncated_value FROM dual;

NO.46 How does SQL handle NULL values in arithmetic expressions?

NO.47 Which type of join returns all rows from the left table, even if there are no matches in the right table?

NO.48 How can a synonym benefit database design?

NO.49 What does the UNION ALL operation do when selecting matching columns from different tables?
SELECT employee_id, salary FROM employees
UNION ALL
SELECT employee_id, bonus FROM bonuses;

NO.50 Which function is used to extract the year from a date in SQL?

NO.51 Which SQL JOIN keyword retrieves all rows from both tables, including those without matches?

NO.52 Which data dictionary view lists all indexes created by the current user?

NO.53 What is the default order of evaluation when multiple SET operators are used in a query?

NO.54 Which type of subquery returns exactly one value?

NO.55 What will the following query return?
SELECT EXTRACT(YEAR FROM CURRENT_DATE) AS year FROM dual;

NO.56 Which SQL clause is used to specify the source table in a query?

NO.57 Which component of an ERD (Entity-Relationship Diagram) represents the attributes of an entity?

NO.58 What happens if a DELETE statement is executed without a WHERE clause?

NO.59 What will the following query result in?
SELECT e.employee_id, e.manager_id
FROM employees e
WHERE e.manager_id IS NOT NULL;

NO.60 What is the primary purpose of a primary key in a relational database?