Free Oracle AI Database SQL AssociatePractice Test

Which statement best describes the relationship between a primary key and a foreign key in a relational database?

What is the correct order of execution for SQL clauses in a SELECT statement?

A database contains an EMPLOYEES table with columns: EMPLOYEE_ID, FIRST_NAME, LAST_NAME, SALARY, and DEPARTMENT_ID. Which normalization form violation would occur if a DEPARTMENT_NAME column were added directly to the EMPLOYEES table?

What type of constraint ensures that a column cannot contain NULL values?

A developer needs to understand the difference between TRUNCATE and DELETE commands. Which statement accurately describes a key difference?

Given a query: SELECT employee_id, first_name FROM employees WHERE department_id = 50 ORDER BY first_name; Which clause determines which rows are included in the result set?

A database administrator needs to retrieve employees who work in departments 10, 20, or 30. Which WHERE clause is most efficient and follows best practices?

What will be the result of the following query: SELECT first_name, last_name FROM employees WHERE last_name LIKE '_a%';

A report requires displaying employees from the EMPLOYEES table along with their department names from the DEPARTMENTS table. Some employees have no assigned department (NULL department_id). Which join type ensures all employees are displayed, even those without a department?

Examine this query: SELECT department_id, COUNT(*) FROM employees GROUP BY department_id HAVING COUNT(*) > 5; What is the purpose of the HAVING clause in this query?

A complex query requires retrieving employees whose salary is greater than the average salary of their department. Which SQL construct is most appropriate?

What is the difference between UNION and UNION ALL when combining result sets from multiple SELECT statements?

A developer executes multiple INSERT statements to add employee records. After reviewing the data, they notice errors and want to undo all changes. Which command should be used?

A transaction involves updating employee salaries, inserting audit records, and deleting old records. The developer wants to create a point after the salary updates to potentially roll back only the subsequent operations. Which statement should be used?

An UPDATE statement needs to increase salaries by 10% for employees in department 50, but only if their current salary is below 5000. Which statement is correct?

A developer is performing a multi-row INSERT using a subquery: INSERT INTO high_earners SELECT * FROM employees WHERE salary > 10000; What happens if an employee record in the subquery violates a constraint in the high_earners table?

Which function would you use to convert a string '2024-01-15' to a DATE data type in Oracle?

A query needs to display employee names in the format 'SMITH, JOHN' (last name, comma, space, first name) from separate LAST_NAME and FIRST_NAME columns. Which function should be used?

When using the NVL function in Oracle, which statement is true?

A database design requires a table to store product information with a unique product code that automatically generates sequential values. Which schema object would be most appropriate to generate these values?