Database Languages in DBMS

 Database Languages kya hoti hain?

Simple shabdon mein:

Database Languages woh special languages hoti hain jinse hum databases ko create, manage, control aur data ko handle karte hain.

Jaise hum English ya Hindi mein ek dusre se baat karte hain, waise hi DBMS ko databases ke saath communicate karne ke liye special languages chahiye hoti hain.

 Database Languages ki zarurat kyun hoti hai?

• Database ka structure banane ke liye (jaise table create karna).

• Data ko insert, delete, update aur retrieve karne ke liye.

• Database ke security aur access ko control karne ke liye.

• Transactions ko manage karne ke liye.

Agar yeh languages na hoti, toh database ko manage karna bahut mushkil hota!

 Types of Database Languages

Database Languages mainly 4 types ki hoti hain:

 1. Data Definition Language (DDL)

DDL ka use hum database ke structure ko banane aur modify karne ke liye karte hain.

 Examples:

• CREATE: Naya table banana

• ALTER: Existing table mein changes karna

• DROP: Table ko delete karna

 Example Query:

 Yahan hum ek Student naam ka naya table bana rahe hain.

 2. Data Manipulation Language (DML)

DML ka use hum data ko manage karne ke liye karte hain.

 Examples:

• INSERT: Naya data add karna

• UPDATE: Purana data change karna

• DELETE: Data delete karna

• SELECT: Data ko retrieve (nikalna) karna

 Example Query:

 Is command se ek naya student record database mein add hoga.

 3. Data Control Language (DCL)

DCL ka use database mein permissions dene aur access control karne ke liye hota hai.

 Examples:

• GRANT: Kisi user ko permission dena

• REVOKE: Kisi user se permission wapas lena

 Example Query:

 Isse hum user1 ko Student table ko dekhne ki permission de rahe hain.

 4. Transaction Control Language (TCL)

TCL ka use transactions ko handle karne ke liye hota hai.

 Examples:

• COMMIT: Changes ko permanently save karna

• ROLLBACK: Changes ko undo karna

• SAVEPOINT: Transaction mein temporary save point banana

 Example Query:

 Isse sare changes database mein permanently save ho jayenge.

 Ek Simple Diagram se Samjho:

 Real-Life Example:

Socho aap ek nayi library open kar rahe ho:

 Short Summary Table:

 Important Points:

• DDL se hum tables banate aur badalte hain.

• DML se hum data ko insert, update, delete karte hain.

• DCL se hum users ko access dete ya lete hain.

• TCL se hum transactions ko save ya cancel karte hain.