# Query Processing and Optimization

##### Video Lessons & Revision Notes

Query Processing - Basic Concepts, Query Cost and Selection Algorithms
1. Query Processing - Basic Concepts, Query Cost and Selection Algorithms
In this 56 mins Video Lesson
Introduction, Query Processing Process, Measures of Query Cost, Disk Access Costs, Selection: Algorithms, Complex Selections: Algorithms, and other topics.
Query Processing - Sorting Algorithms and Nested Loop Join
2. Query Processing - Sorting Algorithms and Nested Loop Join
In this 45 mins Video Lesson
Sorting: Algorithms, External Sort/ N-way Merge, Join Algorithms, Nested Loop Join, and other topics.
Query Processing - More Join Algorithms
3. Query Processing - More Join Algorithms
In this 47 mins Video Lesson
Block Nested Loop Join, Index Nested Loop Join, Merge Join, Hash Join, and other topics.
Query Processing - Complex Joins, Duplicate Elimination and other operations Algorithms
4. Query Processing - Complex Joins, Duplicate Elimination and other operations Algorithms
In this 47 mins Video Lesson
Hash Join Algorithm Explanation, Hash Join: Restriction on 'n', Recursive Partitioning, Complex Joins: Algorithms, Duplicate Elimination: Algorithms, Projections: Algorithm, Aggregation: Algorithms, Set Operations: Algorithms, Outer Join: Algorithms, Modified Merge Join, Hash Join, and other topics.
Query Processing - Evaluation of Expression
5. Query Processing - Evaluation of Expression
In this 25 mins Video Lesson
Evaluation Of an Expression, Materialization, Pipelining, and other topics.
Query Optimization - Equivalence of Expressions and Cost Based Optimizations
6. Query Optimization - Equivalence of Expressions and Cost Based Optimizations
In this 46 mins Video Lesson
Introduction, Equivalence of Expressions, Equivalence Rules, Minimal set , Cost based optimizations, and other topics.
Query Optimization - Heuristics Based Optimizations
7. Query Optimization - Heuristics Based Optimizations
In this 44 mins Video Lesson
Heuristics based Optimization, Algorithm, Example , and other topics.

### Revision Notes

Overview, Measures of query cost, Selection and join operations, Evaluation of Expressions, Introduction to Query Optimization, Estimation,Transformation of Relational Expressions