SQL - Complete Summary - Part 2 | DBMS | With NOTES | Deepak Poonia

SQL Complete Summary & GATE PYQs -    • DBMS: Compact Course & GATE PYQs | Relatio...   DBMS Compact Course & GATE PYQs:    • DBMS: Compact Course & GATE PYQs | Relatio...   Annotated Notes of this session: https://shorturl.at/JlYwg Join GO Classes - The Most Recommended Coaching for GATE CS, DA Exam Preparation. ➤ Join GO Classes #GateCSE Complete Course: https://www.goclasses.in/courses/GATE... ➤ Join GATE CSE+DA Combo Course: https://www.goclasses.in/courses/GATE... ➤ Join GO Classes #GateDA Complete Course: https://www.goclasses.in/courses/GATE... ➤ Join GO Classes TEST Series for GATE CS, DA: https://www.goclasses.in/s/store/cour... ➤ Download GO Classes Android APP: https://play.google.com/store/apps/de... ➤ GO Classes GATE DA YouTube Channel:    / @goclassesforgateda   ---------------------------------------------------- #GoClasses Website : https://www.goclasses.in/ GO Classes ALL Links : https://linktr.ee/goclasses ---------------------------------------------------- ➤ Join GO Classes Telegram Channel & Group for GATE CS/DA Doubts Discussions: 1. https://t.me/GoClasses_CSE 2. https://t.me/GATECSE_Goclasses ---------------------------------------------------- ➤ Watch Complete Discrete Mathematics and Complete Engineering Mathematics Courses on GO Classes (FREE for ALL learners): https://www.goclasses.in/s/store/cour... ➤ Download GATEOverflow GATE PYQs PDFs (Previous Years Questions of GATE CS, DA) here (FREE): https://github.com/GATEOverflow/GO-PDFs ---------------------------------------------------- Feel free to Contact Us for any query. ➤ GO Classes Contact, WhatsApp: (+91) 63025 36274 ➤ GO Classes Mail ID : [email protected] Content of this lecture: 00:00 - SQL Summary Part 2 02:12 - Null Values: Definition & Use Cases 06:15 - Arithmetic Operations with Null 10:25 - Aggregate Functions with Null Values 12:00 - Count(*) vs Count(Attribute) 16:55 - Aggregate Functions with DISTINCT 19:20 - Aggregate Functions on Empty Tables 29:00 - Comparison Operators & Nulls 31:43 - 3-valued logic for evaluating NULL in SQL 33:00 - Three-Valued Logic (True, False, Unknown) 35:50 - Difference Between Null and Unknown 41:40 - Trick to Remember Logic with Unknown 51:17 - Behavior of WHERE Clause with Nulls in SQL WHERE Clause in case of Null Values in SQL - Tuple Selection in case of Null values in SQL 01:00:16 - IS NULL and IS NOT NULL Operators 01:10:30 - Practice Questions: Null Values 01:19:00 - Definition of Duplicate Tuples with Nulls 01:25:10 - GROUP BY Clause: Syntax & Concept 01:27:40 - Purpose of GROUP BY (Group-wise Summary) 01:33:20 - How to Identify Grouping Attributes 01:44:15 - Handling Null Values in GROUP BY 01:47:35 - SELECT Clause Rules with GROUP BY (SQL-92) 01:55:50 - Conceptual Order of Evaluation 02:10:20 - Complex GROUP BY Examples (with WHERE) 02:28:29 - GROUP BY, Without Aggregation, is equivalent to SELECT DISTINCT GROUP BY, without Aggregation, is Valid, But Useless 02:49:40 - Conclusion & Upcoming Topics GO Classes Mail ID : [email protected] #gate2025 #goclasses #computerscience #gateda #gatecs #computer_science #gatecse