CS317 File and Database Systems

Size: px

Start display at page:

Download "CS317 File and Database Systems"

August Williams
5 years ago
Views:

1 CS317 File and Database Systems Lecture 2 DBMS DDL & DML Part-1 September 3, 2017 Sam Siewert

MySQL on Linux (LAMP) Skills http://dilbert.

2 MySQL on Linux (LAMP) Skills DBMS DDL & DML Part-1 (Definition of and Manipulation of Data) Sam Siewert 2

3 MySQL on PRClab Verified? Required for all Exercises, So Make Sure it s Working Basic MySQL Exploration on PRClab (and File system) Goals for Assignment #1 Test Access and MySQL Account Learn Basic SQL Commands and Explore DB Learn Basic Linux File System Commands and Explore Analyze Volume Use by Files Describe Advantages of DBMS over File Systems Describe Advantages of File Systems over DBMS Describe How Facebook Might Use both DBMS and File Systems to Handle Structured and Un-structured Data Sam Siewert 3

4 Exploring Sakila Tables: rental, film, customer, inventory rental: [customer_id], [inventory_id] (where return_date is NULL) -> customer: customer_id -> inventory: inventory_id [film_id] Film: film_id (where INTERVAL film.rental_duration DAY < CURRENT_DATE()) All rentals still out Customers that have rental Sam Siewert 4

5 Oracle s Answer Flims Rented Out Requires an INNER JOIN (We have not studied yet) Where rental.return_date is NULL Where rental_date + film.rental_duration < TODAY Sam Siewert 5

6 Some Example MySQL Hands On Log in Which databases are available? Choose one Start working with it Show tables in DB Query tables Add new rows to tables (data instances) Modify column entries in rows %mysql -u siewerts -p Enter password: Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 473 Server version: MySQL Community Server (GPL) by Remi mysql> show databases; Database information_schema budinadb sakila vismdb whismansdb rows in set (0.00 sec) mysql> use sakila; Reading table information for completion of table and column names You can turn off this feature to get a quicker startup with -A Database changed mysql> show tables; Tables_in_sakila actor actor_info staff staff_list store rows in set (0.00 sec) Sam Siewert Mysql> 6

7 More Example MySQL Hands On For Sakila DB (selected on previous slide) Show Columns Used in a Table (Schema) Show Rows in the Table (Data) Limit or Filter the Results Returned from the Query So Far, We are Using only 1 Table at Time Can we Query for Data from 2 Tables Correlated by a Field? Read Chapter 2 & 3 in Connolly-Begg mysql> show columns from city; Field Type Null Key Default Extra city_id smallint(5) unsigned NO PRI NULL auto_increment city varchar(50) NO NULL country_id smallint(5) unsigned NO MUL NULL last_update timestamp NO CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP rows in set (0.00 sec) mysql> SELECT * FROM city limit 3; city_id city country_id last_update A Corua (La Corua) :45:25 2 Abha :45:25 3 Abu Dhabi :45: rows in set (0.00 sec) mysql> Sam Siewert 7

8 For Discussion DBMS vs. File System (read DMBS Chapter #1) Come to Class Prepared to Discuss Why is DBMS Better then File System Why do we Use File Systems still? What is NoSQL? (Not in Book, Structured vs. Unstructured Data? For Discussion Image Files JPG, PNG Video Files - MPEG Facebook Account User Facebook User Friends and Likes Assignment #1 Discussion I will Post Every Other Wednesday, We ll Discuss, Due Following Week on Friday Late Assignments 10% Penalty for Monday Turn-in, After Monday, only with Instructor Permission Sam Siewert 8

9 For Discussion Coordinating Structured and Un-structured Data Databases Files (Images, Digital Video, Documents) E.g Assignment #1 Due this Friday Late Assignments 10% Penalty for Monday Turn-in, After Monday, only with Instructor Permission Read DBMS Chapters 2 & 3 Sam Siewert 9

10 Connolly-Begg Chapter 2 Discussion & Examples Sam Siewert 10

11 Database Management System (DBMS) A software system that enables users to define, create, maintain, and control access to the database. (Database) application program: a computer program that interacts with database by issuing an appropriate request (SQL statement) to the DBMS. Be Clear on Data Manipulation Language and Query Language (Chapter 2) DML has larger scope than SQL and includes DBMS User Management, Access Control, Import/Export, More than just Query SQL In Depth Chapters 6 to 9, Appendix I Pearson Education 2014

12 Birth of DBMS & RDBMS CODASYL Conference on Data Systems Languages ( s) COBOL Common Business Oriented Language E.F. Codd Paper (on Canvas and Web Page), Formalization of earlier work Landmark paper (we will read in Assignment #2) Relational Calculus Codd s Theorem Relational Algebra (imperative) and Relational Calculus (logical) Modern RDBMS and ODBMS NoSQL, Big Data, Structured/Unstructured - Current

13 Three Tier DBMS Architecture Connolly-Begg (ANSI-SPARC) 1. All users should be able to access same data. 2. A user s view is immune to changes made in other views. 3. Users should not need to know physical database storage details. Pearson Education 2014

14 ANSI-SPARC ANSI-SPARC (ANSI Standards Planning and Requirements Committee) 1975 Logical Design External Level User s View, relevant to each user (student, faculty, records and registration, ) ERNIE Campus Solutions ERNIE CS Student Center Describes portion of database relevant to a user Conceptual Level Community view of a database MySQL show databases; show tables; Describes the data stored in a database and realtionships Internal Level and Physical Design Describes how data is stored Sam Siewert 14

15 Differences between Three Levels of ANSI- SPARC Architecture Connolly-Begg Pearson Education

16 Data Independence and the ANSI- SPARC Three-Level Architecture (Connolly-Begg) Pearson Education

17 MySQL Example External View PHPadmin Page for Sakila Conceptual Schema for Sakila Columns in Tables in DB Internal View MyISAM, InnoDB (E.g. world DB) mysql> show columns from city; Field Type Null Key Default Extra city_id smallint(5) unsigned NO PRI NULL auto_increment city varchar(50) NO NULL country_id smallint(5) unsigned NO MUL NULL last_update timestamp NO CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP rows in set (0.00 sec) mysql> SELECT * FROM city limit 3; city_id city country_id last_update A Corua (La Corua) :45:25 2 Abha :45:25 3 Abu Dhabi :45: rows in set (0.00 sec) mysql> Sam Siewert 17

on command line (http://dev.mysql.com/doc/refman/5.0/en/retrieving-data.

18 Nice Learning Trick Use the PHPadmin page Browse a DB with Point and Click Note the constructed MySQL command for Select data or Show structure, Copy and Paste Play with variants on command line ( ) Great way to teach yourself MySQL along with Refman Example DBs - Sam Siewert 18

Alternative to MobaXterm and Putty for Command Line Putty is Excellent for PRClab Basic Connection Cygwin for personal equipment, provides Unix/Linux command shell for Windows Emulation for

19 Alternative to MobaXterm and Putty for Command Line Putty is Excellent for PRClab Basic Connection Cygwin for personal equipment, provides Unix/Linux command shell for Windows Emulation for PRClab Linux Simpler than Virtual-Box + Linux Better Cut and Paste (main reason I use) download and run setup-x86.exe Add OpenSSH to your Cygwin download Sam Siewert 19

20 Database Languages Data Definition Language (DDL) Allows the DBA or user to describe and name entities, attributes, and relationships required for the application plus any associated integrity and security constraints. MySQL Create Table Full DDL Syntax (Logical & Physical) DDL in MySQL, both Logical and Physical Specification Physical DDL Specifications Storage Engine Selection InnoDB - MyISAM - Memory - MySQL Create Database and Table with Logical Focus Pearson Education

21 Database and Table Creation Focus on Logical (simple table creation for logical schema) Sam Siewert 21

22 Database Languages Data Manipulation Language (DML) Provides basic data manipulation operations on data held in the database. Procedural DML allows user to tell system exactly how to manipulate data. Non-Procedural DML allows user to state what data is needed rather than how it is to be retrieved. Fourth Generation Languages (4GLs) Pearson Education

23 Data Model Integrated collection of concepts for describing data, relationships between data, and constraints on the data in an organization. Data Model comprises: a structural part; a manipulative part; possibly a set of integrity rules. Pearson Education

24 Data Model Purpose To represent data in an understandable way. Categories of data models include: Object-based Record-based Physical. Pearson Education

25 Data Models Object-Based Data Models Entity-Relationship Semantic Functional Object-Oriented. Record-Based Data Models Relational Data Model Network Data Model Hierarchical Data Model Physical Data Models Pearson Education

26 Relational Data Model Pearson Education

27 Network Data Model Pearson Education

28 Hierarchical Data Model Pearson Education

29 Conceptual Modeling Conceptual schema is the core of a system supporting all user views. Should be complete and accurate representation of an organization s data requirements. Conceptual modeling is process of developing a model of information use that is independent of implementation details. Result is a conceptual data model. Pearson Education

30 Functions of a DBMS Data Storage, Retrieval, and Update. A User-Accessible Catalog. Transaction Support. Concurrency Control Services. Recovery Services. Pearson Education

31 Functions of a DBMS Authorization Services. Support for Data Communication. Integrity Services. Services to Promote Data Independence. Utility Services. Pearson Education

32 System Catalog Repository of information (metadata) describing the data in the database. One of the fundamental components of DBMS. Typically stores: names, types, and sizes of data items; constraints on the data; names of authorized users; data items accessible by a user and the type of access; usage statistics. Pearson Education

33 Components of a DBMS Pearson Education

34 Components of Database Manager Pearson Education

CS317 File and Database Systems

CS317 File and Database Systems http://dilbert.com/strips/comic/1995-10-11/ Lecture 5 More SQL and Intro to Stored Procedures September 24, 2017 Sam Siewert SQL Theory and Standards Completion of SQL in