DBMS
DBMS Part-1
- DBMS Introduction
- DBMS Architecture
- Database Approach vs Traditional File System
- Advantages of DBMS
- Data Models in DBMS
- Schemas in DBMS
- Instances in DBMS
- Data Independence in DBMS
- Database Languages in DBMS
- Interfaces in DBMS
- Structure of DBMS
- Functions of DBA and Designer
- Entities and Attributes in DBMS
- ER Diagram in DBMS
- Generalization, Specialization and Aggregation in DBMS
- Converting ER Diagram to Tables in DBMS
- Difference between Object Oriented, Network and Relational Data Models
DBMS Part-2
- Relational Data Model in DBMS
- Keys in DBMS
- SQL Introduction
- DDL(Data Definition Language)
- DML(Data Manipulation Language)
- Integrity Constraints in DBMS
- Complex SQL Queries
- Joins in DBMS
- Indexing in DBMS
- Triggers in DBMS
- Assertions in DBMS
- Relational Algebra in DBMS
- Tuple Relational Calculus in DBMS
- Domain Relational Calculus in DBMS
DBMS Part-3
- Introduction to Normalization in DBMS
- Normal Forms in DBMS
- Functional Dependency in DBMS
- Decomposition in DBMS
- Dependency Preserving Decomposition in DBMS
- Lossless Join Decomposition in DBMS
- Problems with Null Values and Dangling Tuples
- Multivalued Dependency in DBMS
- Query Optimization in DBMS
- Algorithms for Select, Project and Join Operations in DBMS
- Query Optimization Methods in DBMS
DBMS Part-4
- Transactions in DBMS
- Serializability in DBMS
- Recoverability in DBMS
- Recovery Techniques in DBMS
- Log Based Recovery in DBMS
- Checkpoint in DBMS
- Deadlock in DBMS
- Concurrency Control in DBMS
- Lock Based Protocol in DBMS
- Timestamp Based Protocol in DBMS
- Validation Based Protocol in DBMS
- Multiple Granularity in DBMS
- Multi-Version Concurrency Control(MVCC) in DBMS
- Recovery with Concurrent Transactions in DBMS
DBMS Part-5
Distributed Database kya hota hai?
Distributed Database ek aisa database hota hai jisme data ek hi jagah pe nahi, balki multiple locations (ya computers) pe stored hota hai.
Lekin user ke liye ye sab ek hi database jaisa lagta hai.
Kyun use karte hain Distributed Database?
Socho ek company ke offices Delhi, Mumbai aur Bangalore mein hain.
Agar har office ka data apne-apne system mein store ho, aur sabhi offices ek dusre ka data easily access kar saken — to is setup ko hi Distributed Database System kehte hain.
Example
| City/Branch | Store kiya gaya Data |
|---|---|
| Delhi | North India ke customers ka data |
| Mumbai | West India ke customers ka data |
| Bangalore | South India ke customers ka data |
Lekin ek Mumbai user Bangalore ka data bhi access kar sakta hai — bina tension ke.
Types of Distributed Databases
1. Homogeneous Distributed DBMS
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Sabhi locations same DBMS software use karte hain.
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Manage karna easy hota hai.
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Example: Har branch MySQL use kar rahi ho.
2. Heterogeneous Distributed DBMS
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Har location alag DBMS use kar sakti hai.
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Complex hota hai.
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Example: Delhi mein Oracle aur Bangalore mein PostgreSQL ho.
Key Features
| Feature | Kya karta hai |
|---|---|
| Location Transparency | User ko nahi pata data kahan store hai |
| Replication | Same data multiple jagah copy karke rakha jata hai |
| Fragmentation | Data ko parts mein todkar alag jagah store karna |
Fragmentation ke Types
a. Horizontal Fragmentation
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Data ke rows ko alag-alag sites pe store karte hain.
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Example: Delhi mein North customers, Bangalore mein South customers.
b. Vertical Fragmentation
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Data ke columns alag-alag jagah store hote hain.
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Example: Name, Email Delhi mein; Transactions Mumbai mein.
c. Mixed Fragmentation
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Rows aur columns dono tod ke distribute kiye jate hain.
Fayde (Advantages)
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Zyada Reliable – Agar ek site down ho gayi, baaki kaam karte rahenge.
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Fast Access – Data near user hota hai, isliye queries fast hoti hain.
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Scalable – Aap easily naye database add kar sakte ho.
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Modular – Har site ko alag se maintain kar sakte ho.
Nuksaan (Disadvantages)
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Complex System – Banane aur samajhne mein thoda tough.
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Data Sync Dikkat – Data sab sites pe same rakhna mushkil hota hai.
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Network pe Depend – Internet ya network down hua toh dikkat ho sakti hai.
Real-Life Example
Socho Google ya Netflix — unka data duniya bhar ke servers mein stored hota hai.
Lekin tum jab bhi Google search ya Netflix pe video dekhte ho, tumhe lagta hai ki sab ek jagah se aa raha hai.
Wahi hota hai Distributed Database System!
Summary
| Term | Meaning |
|---|---|
| Distributed DBMS | ek aisa database system jo data ko multiple locations par store karke ek hi system jaise manage karta hai |
| Location Transparency | User ko pata nahi hota data kahan hai |
| Fragmentation | Data ko parts mein todna aur store karna |
| Replication | Same data multiple jagah pe hona |
| Homogeneous | Same DBMS software har site pe |
| Heterogeneous | Alag DBMS software har site pe |