Understanding Database Management

What is a primary key in database design?

• A primary key is used to store large binary files in a database.

• A primary key is a unique identifier for a record in a database table.

• A primary key can contain duplicate values in a table.

• A primary key is a type of foreign key in a database.

Explain the concept of normalization.

• Normalization is the process of increasing data redundancy.

• Normalization refers to the method of encrypting data for security purposes.

• Normalization is a technique used to visualize data in charts and graphs.

• Normalization is the process of organizing data in a database to reduce redundancy and improve data integrity.

What is the purpose of a foreign key?

• To delete records from a table.

• To store unique values in a column.

• To create a new table in the database.

• The purpose of a foreign key is to maintain referential integrity between two tables.

Define the term 'entity' in the context of databases.

• An entity is a type of database management system.

• An entity refers to a database query.

• An entity is a method for data retrieval.

• An entity is a distinct object or thing in a database that can be identified and has attributes.

What does SQL stand for?

• Structured Query Language

• Standard Query Language

• Structured Query List

• Simple Query Language

How do you select all records from a table in SQL?

• SELECT ALL FROM table_name;

• SELECT * FROM table_name;

• FETCH * FROM table_name;

• GET * FROM table_name;

What is the function of the WHERE clause in SQL?

• The WHERE clause groups records by specified fields.

• The WHERE clause filters records based on specified conditions.

• The WHERE clause sorts records in ascending order.

• The WHERE clause defines the structure of a database table.

Explain the difference between INNER JOIN and LEFT JOIN.

• INNER JOIN returns all rows from both tables; LEFT JOIN returns only unmatched rows from the left.

• INNER JOIN includes all rows from the right table; LEFT JOIN excludes unmatched rows from the left.

• INNER JOIN returns matched rows only; LEFT JOIN returns all rows from the left table and matched rows from the right.

• INNER JOIN and LEFT JOIN are identical in functionality and output.

What is a database schema?

• A database schema is a type of software application.

• A database schema is a programming language used for data manipulation.

• A database schema is a collection of user accounts and permissions.

• A database schema is a blueprint that outlines the structure of a database, including tables, fields, and relationships.

How do you insert a new record into a table using SQL?

• INSERT INTO table_name VALUES (value1, value2);

• INSERT table_name (column1, column2) SET (value1, value2);

• INSERT INTO table_name (column1, column2) VALUES (value1, value2);

• ADD RECORD INTO table_name (column1, column2) VALUES (value1, value2);