View kya hota hai? (simple definition)
View = saved SELECT query ka naam.
Jo tum bar-bar likhte ho, usko ek baar define karke view bana do.
Important: View apna data store nahi karta (normally).
- View me “rows/columns” dikhte hain, but wo base tables se live aate hain.
- Isliye tumhara point correct: “view is a virtual table.”
1) View vs Table (core difference)
Table
- Data physically store hota hai
INSERT/UPDATE/DELETE direct table me hota hai
View
- Data store nahi (definition store hoti)
- Base tables change → view output automatically change
Example:
orders table me new order insert hua
order_summary_view me woh automatically reflect ho jaayega
2) View kyu use karte hain? (real-world reasons)
A) Reusability