SQL Views

A view is a saved query that you can use like a virtual table. It does not usually store its own copy of the data; it reads from the underlying tables when queried.

Why use a view?

• Hide complex joins behind a simpler name.
• Expose only selected columns to users or reports.
• Reuse a query in many places.
• Make reporting queries easier to read.

Syntax

CREATE VIEW view_name AS
SELECT column1, column2
FROM table_name
WHERE condition;

Example

Create a view with active customers:

CREATE VIEW active_customers AS
SELECT customer_id, customer_name, email
FROM customers
WHERE status = 'active';

Then query the view:

SELECT customer_name, email
FROM active_customers
ORDER BY customer_name;

Common mistakes

• Assuming a view is always a physical table.
• Changing underlying tables without checking the views that depend on them.
• Putting too much hidden logic in views without documenting it.

Related topics

See also SQL CREATE VIEW, SQL SELECT and the SQL Formatter.