MySQL Views

MySQL Views – Complete Tutorial

In MySQL Views is a virtual table based on the result of an SQL query.
It does not store data physically; it stores only the query definition.

Views are mainly used for security, simplicity, and reusability.

MySQL

What is a View in MySQL?

A View:

Is created using a SELECT query
Looks like a table
Always shows latest data from base tables

Think of a view as a saved query.

Why Use Views?

Hide complex SQL queries
Improve security (show limited columns)
Reuse SQL logic ✔ Simplify reporting queries
Improve readability

Syntax to Create a View

Simple View Example

Table: `students`

Create View

Use View

Acts like a table
Data updates automatically

View with Multiple Tables (JOIN)

View with Aggregate Function

Updating Data Through a View

Possible if view is simple

Example

Cannot update views with:

JOIN
GROUP BY
DISTINCT
Aggregate functions

ALTER View

Used to modify an existing view.

Drop View

Check View Definition

Views vs Tables (Very Important)

Feature	View	Table
Data storage	No	Yes
Speed	Slightly slower	Faster
Security	High	Normal
Update	Limited	Full
Memory	Less	More

Interview Questions & MCQs

Q1. What is a view in MySQL?

Answer:
A view is a virtual table created from a SELECT query.

Q2. Does a view store data?

A) Yes
B) No

Answer: B

Q3. Which command creates a view?

A) MAKE VIEW
B) CREATE VIEW
C) ADD VIEW
D) INSERT VIEW

Answer: B

Q4. Can we update data through a view?

A) Always
B) Never
C) Sometimes
D) Only SELECT

Answer: C

Q5. Which clause makes a view non-updatable?

A) WHERE
B) JOIN
C) GROUP BY
D) DISTINCT

Answer: C
(Also JOIN, DISTINCT, aggregates)

Q6. How to delete a view?

Q7. What is the main advantage of views?

A) Faster than tables
B) Reduce memory
C) Security & simplicity
D) Data backup