September 4, 2018 Sam Siewert

CS317File and Database Systems

Lecture 2 – DBMS – DDL & DMLPart-1

MySQL on Linux (LAMP) Skills

DBMS DDL & DML – Part-1(Definition of and Manipulation of Data)

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http://dilbert.com/strips/comic/2010-08-02/ - UFR=? Uniform Financial Report

MySQL on PRClab1 – Verified?Required for all Exercises, So Make Sure it’s WorkingBasic MySQL Exploration on PRClab1 (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 (“ls”, “lsof”, – Analyze Volume Use by Files (e.g. “df -h”, “du”, “ls -lS -R”, etc.)– Describe Advantages of DBMS over File Systems– Describe Advantages of File Systems over DBMS– Understand How Facebook Might Use both DBMS and File Systems to Handle

Structured and Un-structured Data

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DBs and tables - InnoDB, MyISAM, ISAMDefault is InnoDB per table

Exploring Sakila - AdminerTables: rental, film, customer, inventoryrental: [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())

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All rentals still outCustomers that have rental

Adminer - Sakila exploration

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myPHPAdmin (similar to Adminer)Useful for insert and delete DB maintenanceCut and paste SQL into command lineSQL editing help minimalRecommend Adminer while learning SQLSeems slower than Adminer was and a little less friendly

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Describe rental ->

Exploring film table on command lineFirst describe the table columns (attributes, domain, integrity, insert features) - shown as rows

Query for data “tuples” or “rows” for all fields

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More command line explorationAll fields from film table is more than we want, so use a “projection” to select specific columns

1000 films, so use “where” clause (implicit join) to match tuples with attribute data ranges and “limit” to first 5

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Oracle’s Answer – “Flims Rented Out”Requires an INNER JOIN (We have not studied yet)Where rental.return_date is NULLWhere rental_date + film.rental_duration < TODAY

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Before using JOIN, try WHEREAttempt to list late movies meeting specific criteria with WHERE clauses (implicit join)

select customer.last_name,address.phone,film.title, rental_datefrom rental,customer,address,film,inventorywhere rental.customer_id = customer.customer_idand customer.address_id = address.address_idand rental.inventory_id = inventory.inventory_idand inventory.film_id = film.film_idand rental_date < current_date() limit 5;

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Some Example MySQL – Hands OnLog inWhich databases are available?Choose oneStart working with it– Show tables in DB– Query tables– Add new rows to

tables (data instances)– Modify column entries

in rows

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%mysql -u siewerts -pEnter password:Welcome to the MySQL monitor. Commands end with ; or \g.Your MySQL connection id is 473Server version: 5.5.38 MySQL Community Server (GPL) by Remi

mysql> show databases;+--------------------+| Database |+--------------------+| information_schema || budinadb |…| sakila |…|| vismdb || whismansdb |+--------------------+21 rows in set (0.00 sec)

mysql> use sakila;Reading table information for completion of table and column namesYou can turn off this feature to get a quicker startup with -A

Database changedmysql> show tables;+----------------------------+| Tables_in_sakila |+----------------------------+| actor || actor_info |…| staff || staff_list || store |+----------------------------+23 rows in set (0.00 sec)

Mysql>

More Example MySQL – Hands OnFor 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 QuerySo Far, We are Using only 1 Table at TimeCan we Query for Data from 2 Tables Correlated by a Field?Read Chapter 2 & 3 in Connolly-Begg

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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 |+-------------+----------------------+------+-----+-------------------+-----------------------------+4 rows in set (0.00 sec)

mysql> SELECT * FROM city limit 3;+---------+--------------------+------------+---------------------+| city_id | city | country_id | last_update |+---------+--------------------+------------+---------------------+| 1 | A Corua (La Corua) | 87 | 2006-02-15 04:45:25 || 2 | Abha | 82 | 2006-02-15 04:45:25 || 3 | Abu Dhabi | 101 | 2006-02-15 04:45:25 |+---------+--------------------+------------+---------------------+3 rows in set (0.00 sec)

mysql>

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, http://en.wikipedia.org/wiki/Nosql)– Structured vs. Unstructured Data? – For Discussion

Image Files – JPG, PNGVideo Files - MPEGFacebook Account UserFacebook 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

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For Discussion…Coordinating Structured and Un-structured Data– Databases– Files (Images, Digital Video, Documents)– E.g. http://mercury.pr.erau.edu/~siewerts/extra/images/– http://mercury.pr.erau.edu/~siewerts/extra/video/– http://mercury.pr.erau.edu/~siewerts/extra/documents/– http://mercury.pr.erau.edu/~siewerts/extra/code/

Assignment #1 – Due this Friday– Late Assignments – 10% Penalty for Monday Turn-in, After

Monday, only with Instructor Permission

Read DBMS Chapters 2 & 3

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Connolly-Begg Chapter 2

Discussion & Examples

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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

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Birth of DBMS & RDBMSCODASYL – Conference on Data Systems Languages (1959 – 1980’s)– COBOL – Common Business Oriented Language– http://special.lib.umn.edu/findaid/xml/cbi00011.xml

1970 – E.F. Codd Paper (on Canvas and Web Page), http://www.seas.upenn.edu/~zives/03f/cis550/codd.pdf– 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 ODBMSNoSQL, Big Data, Structured/Unstructured - Current

Three Tier DBMS Architecture –Connolly-Begg (ANSI-SPARC)

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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. Different from LAMP 4-Tier / Connector 3-Tier

(Week-1, slide #18) - Abstracted 3-Tier, 4-Tier

ANSI-SPARCANSI-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 SolutionsERNIE CS Student CenterDescribes portion of database relevant to a user

– Conceptual Level – Community view of a databaseMySQL – show databases; show tables;Describes the data stored in a database and realtionships

Internal Level and Physical Design– Describes how data is stored

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Differences between Three Levels of ANSI-SPARC Architecture – Connolly-Begg

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Data Independence and the ANSI-SPARC Three-Level Architecture

(Connolly-Begg)

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MySQL – ExampleExternal View – PHPadmin Page for SakilaConceptual Schema for Sakila– Columns in Tables in DB– http://dev.mysql.com/doc/sakila/en/sakila-structure.html

Internal View – MyISAM, InnoDB (E.g. world DB)

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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 |+-------------+----------------------+------+-----+-------------------+-----------------------------+4 rows in set (0.00 sec)

mysql> SELECT * FROM city limit 3;+---------+--------------------+------------+---------------------+| city_id | city | country_id | last_update |+---------+--------------------+------------+---------------------+| 1 | A Corua (La Corua) | 87 | 2006-02-15 04:45:25 || 2 | Abha | 82 | 2006-02-15 04:45:25 || 3 | Abu Dhabi | 101 | 2006-02-15 04:45:25 |+---------+--------------------+------------+---------------------+3 rows in set (0.00 sec)

mysql>

Nice Learning TrickUse PHPadmin - http://prclab1.erau.edu/phpmyadmin/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

(http://dev.mysql.com/doc/refman/5.0/en/retrieving-data.html )

Great way to teach yourself MySQL along with RefmanExample DBs - http://dev.mysql.com/doc/index-other.html

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Database LanguagesData 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)– http://dev.mysql.com/doc/refman/5.6/en/create-table.html– DDL in MySQL, both Logical and Physical Specification

Physical DDL Specifications– Storage Engine Selection– InnoDB - http://dev.mysql.com/doc/refman/5.6/en/innodb-storage-engine.html– MyISAM - http://dev.mysql.com/doc/refman/5.6/en/myisam-storage-engine.html– Memory - http://dev.mysql.com/doc/refman/5.6/en/memory-storage-engine.html

MySQL – Create Database and Table with Logical Focus– http://dev.mysql.com/doc/refman/5.7/en/database-use.html

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Database and Table CreationFocus on Logical (simple table creation for logical schema)

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Database Languages - Connelly & Begg

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)

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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.

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Data Model

Purpose– To represent data in an understandable way.

Categories of data models include:– Object-based– Record-based– Physical.

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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

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Relational Data Model

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Network Data Model

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Hierarchical Data Model

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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.

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Functions of a DBMS

Data Storage, Retrieval, and Update.

A User-Accessible Catalog.

Transaction Support.

Concurrency Control Services.

Recovery Services.

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Functions of a DBMS

Authorization Services.

Support for Data Communication.

Integrity Services.

Services to Promote Data Independence.

Utility Services.

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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.

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Components of a DBMS

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Components of Database Manager

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