PPT-LECTURE 4 RELATIONAL ALGEBRA

Introduction Relational algebra defines the theoretical way of manipulating table contents through a number of relational operators These relational operators include SELECT or RESTRICT PROJECT. Slide . 1. Relation (Table). name. birth. gpa. grad. Anderson. 1987-10-22. 3.9. 2009. Jones. 1990-4-16. 2.4. 2012. Hernandez. 1989-8-12. 3.1. 2011. Chen. 1990-2-4. 3.2. 2011. VARCHAR(30). DATE. FLOAT. Beginners. to Advanced. Sophia Georgiakaki. AMATYC 2014. Why Flip?. 3 . credits  not enough time to cover content. Success rates 42% or lower. Students claim to understand lecture in class but cannot figure out problems at home. in medical data. Luca Anselma. a. , Paolo Terenziani. b. a. Dipartimento di Informatica, Università di Torino, Torino, Italy. , Email: . anselma@di.unito.it. b. Dipartimento di Informatica, Università del Piemonte Orientale “Amedeo Avogadro”, Alessandria, Italy. . 6.375 Final Project. Ming Liu, . Shuotao. . Xu. Motivation. Today’s Database Management Systems (DBMS): software running on a standard operating system on a general purpose CPU. DBMS frequently used in analytics and scientific computing, but bottlenecked by:. Nothing is so practical as a good theory. Kurt Lewin, 1945. The relational model. Overcame shortcomings of earlier database models. Has a strong theoretical base. Codd was the major developer. Problems with other models. Relational Algebra (Using SQL DML Syntax):. Data Manipulation Language For Relations. Relational Algebra And SQL. SQL is based on relational algebra with many extensions. Some necessary. Some unnecessary. Developing Relational Thinking in the Primary Grades. Relational Thinking. Students who can express a number in terms of other numbers and operations on those numbers hold a . relational understanding of the number. (Spr15). List the name and address of all vendors that provide both hardware and software.. BOTHV = . . HVendorID,SVendorID . (. . . HWFlag=T and SWFlag=T . (. Vendor. )). ANS = . Review. by Eduardo J Ruiz. (Adapted from Fernando . Farfan. Slides). AGENDA. Ch1. Overview of DBMSs. Ch2. Database Design. Ch3. Relational Model. Ch4. Relational Algebra. AGENDA. Ch1. Overview of DBMSs. Today’s Lecture. The Relational Model & Relational Algebra. Relational . Algebra Pt. II . [Optional: may skip]. 2. Lecture 16. 1. The Relational Model & Relational Algebra. 3. Lecture 16 > Section 1. Cse 344 May 7 th – Exam Review Examination Stations Exam Wednesday 9:30-10:20 One sheet of notes, front and back Practice solutions out after class Good luck! Exam Length Production v. Verification 6.830 Lecture 3 Relational Algebra and Normalization 9/13/2017 Relational Algebra Projection π(R, c1, …, cn ) = π c1…c2n R select a subset c1 … cn of columns of R Selection σ ( R , Slide . 1. Relation (Table). name. birth. gpa. grad. Anderson. 1987-10-22. 3.9. 2009. Jones. 1990-4-16. 2.4. 2012. Hernandez. 1989-8-12. 3.1. 2011. Chen. 1990-2-4. 3.2. 2011. VARCHAR(30). DATE. FLOAT. Serge Abiteboul. INRIA Saclay, Collège de France et ENS Cachan. 3/20/12. 1. 3/20/12. 1. 3/20/12. 1. 3/20/12. 1. Recall for first lecture:. Always . question . everything. In industry: to challenge the well established guys .