INFO MAN FINALS

Which SQL SELECT statement would retrieve all employees' names from the table?

• SELECT * FROM Employees;

• SELECT DISTINCT Name FROM Employees;

• SELECT Name FROM Employees;

• SELECT x Name FROM Employees WHERE x = ALL;

Answer explanation

Explanation:

Option A: Incorrect. SELECT * retrieves all columns from the Employees table, not just the employee names.

Option B: Incorrect. DISTINCT removes duplicates, so it will return unique names. However, the question does not ask for distinct names, just all employee names.

Option C: Correct. This query selects only the Name column from the Employees table, retrieving all employee names.

Option D: Incorrect. This query is invalid because the syntax for x Name and WHERE x = ALL is not correct for this context.

Which SQL SELECT statement will retrieve all job roles?

• SELECT role FROM jobs;

• SELECT * FROM job_roles;

• SELECT job_roles FROM employees;

• SELECT job_role FROM jobs;

Which statement accurately describes the SQL DELETE command?

• Remove table schema

• Eliminate all specific columns

• Delete specific row based on condition

• Adds a new record to the table

Which of the following statements about the SQL DELETE statement is true?

• DELETE without a WHERE clause removes all records in the table.

• DELETE cannot be used without a WHERE clause.

• DELETE removes the entire table structure.

• DELETE only removes a single record.

Answer explanation

• Option A: Correct. If you execute the DELETE statement without a WHERE clause, it will remove all rows from the table, but the table structure (schema) remains intact.

Example:

DELETE FROM Employees;

• Option B: Incorrect. While it's recommended to use a WHERE clause to avoid unintended data deletion, DELETE can technically be used without a WHERE clause. It will delete all rows in the table in that case.

• Option C: Incorrect. The DELETE statement only removes rows (data) from the table, not the entire table structure. To remove the table itself, the DROP TABLE statement would be used.

• Option D: Incorrect. The DELETE statement can remove multiple records (rows), not just a single one. It removes records based on the condition specified in the WHERE clause (or removes all if no condition is specified).

What does the following SQL statement DROP TABLE student; do?

• Deletes all records from the student table but keeps the table structure.

• Deletes the student table and all its records from the database permanently.

• Removes all columns from the student table.

• Renames the student table to something else.

What does the following SQL statement do? (VERIFY) DROP TABLE student;

• Deletes the student table and all its data permanently from the database, along with its structure, but the schema as a container remains unaffected.

• Deletes the student table and its data, including the schema itself.

• Deletes only the data in the student table but leaves the table structure intact.

• Deletes the student table and its data, including all other tables in the database.

What is the primary function of BQL?

• To query and manage data within a relational database system.

• To perform mathematical calculations on data in SQL queries.

• To define the structure of a database and its tables.

• To manage user access and permissions in a database.

Answer explanation

Explanation:

• Option A: Correct. BQL (Business Query Language) is typically used in business intelligence systems and data analytics platforms. It allows users to query and manage data stored in a database, often tailored to business operations and reports.

• Option B: Incorrect. While SQL can perform mathematical calculations, BQL is not specifically focused on mathematical operations within queries. It is more about querying data from a business perspective.

• Option C: Incorrect. Defining the structure of a database and its tables is the function of DDL (Data Definition Language) like CREATE, ALTER, etc., not BQL.

• Option D: Incorrect. Managing user access and permissions is the function of DBA (Database Administrator) tools and related SQL commands like GRANT and REVOKE, not BQL.

You manage a database containing information about various products in an e-commerce platform with columns like ProductID, ProductName, Price, and Quantity. You need to increase the price of all products by 10%. Which SQL query will correctly update the prices?

• UPDATE products SET Price = Price + 10;

• UPDATE products SET Price = Price * 1.10;

• UPDATE products SET Price = Price + (10);

• UPDATE products SET Price = Price - 10;

You've been tasked with modifying the stock quantity of a specific product identified by its ProductID. You must reduce the stock quantity of ProductID 102 by 5 units. Which SQL query will correctly accomplish this task?

• UPDATE products SET Quantity = Quantity - 5 WHERE ProductID = 102;

• UPDATE products SET Quantity = 5 WHERE ProductID = 102;

• DELETE FROM products WHERE ProductID = 102;

• INSERT INTO products (ProductID, Quantity) VALUES (102, Quantity - 5);

What is the primary purpose of DDL (Data Definition Language) in SQL?

• To manipulate and query data in a database.

• To define, modify, and remove database structures like tables and schemas.

• To manage database access and user permissions.

• To insert, update, or delete records in a table.