SQL Table Joins Quiz

What is the primary purpose of a relational database?

• To replicate data across tables

• To establish relationships between tables

• To increase redundancy

• To store data as plain text

Which SQL command is used to create a table?

• INSERT

• SELECT

• CREATE TABLE

• DROP TABLE

What does the AUTO_INCREMENT attribute do?

• Automatically updates a row

• Automatically increments a primary key value

• Automatically creates a table

• Automatically joins two tables

Which join type retrieves only rows with matching conditions in both tables?

• LEFT JOIN

• RIGHT JOIN

• INNER JOIN

• FULL OUTER JOIN

What is a Cartesian Product in SQL?

• The result of a SELECT query

• The result of a JOIN without a WHERE clause

• The combination of a LEFT and RIGHT JOIN

• A type of indexing

What does a FOREIGN KEY in one table refer to?

• A primary key in another table

• A column in the same table

• An index in another database

• A secondary key in another table

Which SQL clause specifies the condition for joining two tables?

• ON

• WHERE

• JOIN

• USING

What is the purpose of table aliases in SQL?

• To rename tables permanently

• To temporarily assign alternate names to tables

• To delete tables

• To change table data types

Which of the following does NOT return rows with NULL values in join conditions?

• INNER JOIN

• LEFT JOIN

• RIGHT JOIN

• FULL OUTER JOIN

Which join includes all rows from the left table, even if there are no matches in the right table?

• INNER JOIN

• RIGHT OUTER JOIN

• LEFT OUTER JOIN

• FULL OUTER JOIN