Can you explain the concept of a virtual table and its purpose in databases?

A virtual table (or view) in databases is a logical table that does not store data physically but is generated dynamically based on an SQL query.

Purpose of a virtual table:

• Simplify complex queries: you can create a view with necessary joins and filters, and then access it as if it were a regular table.
• Enhance security: restrict access to certain columns or rows, providing users only with the needed data.
• Abstract the data structure: hide the complexity or implementation details of the database.

Example:

CREATE VIEW active_users AS
SELECT id, name, email
FROM users
WHERE status = 'active';

Now, queries can be made to active_users as if it were a regular table, retrieving only active users.