Core Computer Science Crash Course | All Interview questions covered | Tamil | 2025

Core Computer Science Crash Course | Important Interview questions covered | OS DBMS CN OOPs SQL | Tamil | 2025 DBMS DBMS: Manages data storage, retrieval (MySQL, PostgreSQL). ACID: Atomicity (all or nothing), Consistency (valid states), Isolation (independent transactions), Durability (permanent changes). Normalization Keys: Primary (unique ID), Foreign (relation link), Candidate (potential PK). 1NF: No duplicate columns, atomic values. 2NF: Remove partial dependencies. 3NF: Remove transitive dependencies. Denormalization & DB Types Denormalization: Merge tables for read optimization. DB Types: RDBMS (SQL-based) vs NoSQL (unstructured data). SQL Queries CRUD: SELECT, INSERT, UPDATE, DELETE. JOINS: INNER, LEFT, RIGHT, FULL. GROUP BY, HAVING, Aggregates: COUNT, SUM, AVG, MIN, MAX. OOPs (C++ & Java) Principles: Encapsulation, Inheritance, Polymorphism, Abstraction. Java OOP: Classes, Objects, Interfaces, Multiple Inheritance. Computer Networking Models: OSI (7 layers), TCP/IP (4 layers). Concepts: IP Addressing, Subnetting, DNS, DHCP, NAT, VPN, Firewalls. Protocols: HTTP/HTTPS, FTP, SMTP, VoIP. Security: QoS, Load Balancing, Cloud Computing. OS & System Design Processes & Threads Sync & Concurrency Deadlocks & Scheduling Memory Mgmt & Virtualization Networking & Real-Time OS Security & System Calls Load Balancing & Fault Tolerance Multi-Core Processing & Async I/O 00:00 Intro 00:47 DBMS 01:36 What is DBMS? 02:39 What is Database 03:20 ACID Properties 07:05 Normalisation 10:45 First Normalization Form(1NF) 11:15 Second Normalization Form (2NF) 13:00 Third Normalization Form (3NF) 14:28 Denormalization 15:34 Types of DataBase 16:55 SQL ESsentials 28:00 Transaction and Concurrency Control 33:15 Deadlock 34:25 Indexing 37:08 SQL,NoSQL :- Pros & Cons 38:20 Recap of DBMS 42:25 Cap theorem 46:32 OOPs Intro 47:42 What is OOPs? 55:31 Real world example of OOPs 56:03 Why C++ is not OOP? 57:25 Advantages of using OOPs 58:15 Differences between Classes and Objects 01:00:19 Encapsulation 01:04:15 Inheritance 01:13:54 Ploymorphism 01:19:25 Abstraction 01:26:55 Interfaces and Multiple inheritance 01:31:58 Computer Networks 01:32:37 OSI Layer 01:34:45 TCP/IP Model 01:36:17 Subnetting 01:37:24 DNS (Domain Name System) 01:38:10 DHCP 01:38:47 Routing 01:39:46 Switching 01:40:27 Network Address Translation 01:41:05 Firewall 01:42:05 VPN 01:43:03 HTTP/HTTPS,FTP,SMTP 01:44:44 LAN,MAN,WAN 01:45:24 Wifi 01:45:51 EtherNet 01:46:14 Bandwidth,Latency 01:47:10 Qos 01:47:38 Voice over IP 01:48:42 Cloud Computing 01:49:00 Load Balancing 01:49:51 Network Security 01:50:30 Operation Systems 01:51:00 Process and Threads 01:51:50 Synchronization and Concurrency 01:52:43 DeadLock 01:54:00 Memory Management 01:54:28 Scheduling Algorithms 01:56:30 Filesystem and Storage 01:56:58 IPC 01:58:07 Virtual Memory 01:59:25 Multithreading 02:00:15 Mutex and Semaphores 02:01:25 Kernel vs User Mode 02:02:10 I/O Management 02:02:40 Disc Scheduling Algorithms 02:04:31 File permission and security 02:05:23 Virtualization 02:06:05 Networking 02:06:25 Real Time OS 02:06:57 Security and Protection 02:07:20 System Calls 02:07:43 Load Balancing 02:08:45 Fault Tolerance and Recovery 02:09:14 Multi Core Processing 02:09:59 Asynchronous I/O 02:10:50 Booting Process 02:11:37 Performance & Tuning Whatsapp Channel: https://whatsapp.com/channel/0029VaYIn3NJUM2WPkmJ9I43 Join Membership: https://www.youtube.com/channel/UCVXHYmFar7yArWvkcjxWXuQ/join 📢📢📢📢 Social Media Links 📢📢📢📢 Mentorship 1:1 : https://www.meetmymentor.me/hareesh_rajendran Buy me a coffee ☕️ : https://www.buymeacoffee.com/hareeshrajendran LinkedIn: https://www.linkedin.com/in/hareesh-r/ Instagram: https://www.instagram.com/hareesh_._r/ Facebook: https://www.facebook.com/hareeshprogrammer/ Twitter: https://twitter.com/hareesh_dev GitHub: https://github.com/hareesh-r Curious to know more about me?: https://hareesh.web.app🚀 Your support means the world to me! 🙌 Let's build an awesome community together. 🌍✨