F2023 #14 - Query Planning & Optimization (CMU Intro to Database Systems) 

this topic is difficult

This one blew it out of the park in terms of what to expect when designing/creating a database. Beautiful lecture! Very thankful for the direction that it provides for the way forward. Humbled and thankful team Andy/Jignesh.

great lecture once again.

Timestamps: 1:48 - Example with optimizations 21:49 - Query Optimization 25:45 - Predicate Pushdown 28:37 - Replace Cartesian Product 30:26 - Projection Pushdown 33:48 - Architecture Overview 38:00 - Cost Based Optimization 40:27 - System R Optimizer (Bottom-up) 51:04 - Top-down Optimization 57:10 - Nester Sub-Queries 1:04:00 - Cost Estimation 1:14:00 - Essential Query Optimization Papers

Thank you for lection! Could you elaborate please - what is optimized by DBMS: logical or physical plans? or both? If only logical plans, how DBMS can calculate costs without knowing of exact physical operations behind nodes of query tree?

Thanks for making the great content available online🥰