Database part1-

Course code: ITI131
Course title : Database
PART: 1
Prof. Taymoor Mohamed Nazmy
Dept. of computer science, faculty of computer science, Ain Shams uni.
Ex-vice dean of post graduate studies and research Cairo, Egypt
1

Course Description
• 1-Data, database,
• 2-DBMS, Model architecture,
• 3-Database languages and models,
• 4-Relational database,
• 5-SQL,
• 6,7-E/R digram
• 8-Database design,
• 9-Database integrity
• 10-11Normalization
• 12-Review
• Required text:
• Database system concept, 6th edition , McGraw-hill, 2011.
2

About the lecturer
- Prof. of computer science since 2006,
- Director of Ain Shams information network,
- Vice dean of post graduate studies and research,
- Vice dean of environmental and social affairs,
- Member in editorial board of many Int. journals,
- Member in Scientific committee of many int. conferences
- Executive chair of int. conf. on information and intelligent systems,
- Published more than 60 scientific papers in int. journals and
conference,
Supervised more than 20 master and Ph. D thesis.
3

About the course
• The materials of this course were collected from many resources, include the
reference book, other books, online courses, presentations, and web sites.
• There are many details will be given to simplify topics in this course, however at the
end of the course the most important topics will be highlighted.
• The delivered materials through this presentation is your main resource,
• This presentation will be delivered to you.
• There will be term exams 40%
• Lab 20%
• The final exam 40%
• The exam will include subjective and objective questions,
• Through this course try to extends your knowledge by improving your self learning
capabilities.
4

Important
• Try to continues improve your language by
adding new vocabulary (word meaning),
• Read the lecture more than one time,
• You may got more details from references,
• There are think to remember , and others to
understand.
6

Understand a DBMS and define its components.
Understand the architecture of a DBMS and its levels.
Distinguish between different database models.
Understand the concept of relational database operations
on a relation.
Course objectives
Use Structured Query Language (SQL) to define simple
relations.
Use E/R diagram for modeling relations
7

Structure of complete Course
Database
Fundamentals
Relational
Model
Normalization
Conceptual
Modeling
Query
Languages
Advanced
SQL
Transaction
Management
Java DB
Applications –
JDBC
Data
Mining
0. Intro 1. Design 3. Applications 4. Advanced
Topics
Newbie Users ProfessionalsDesigners
Database course
2. Querying
Developers
8

9
Database Prehistory
Data entry
Storage and retrieval
Query processing
Sorting 9

Stages of Information System
 Stage 0: Manual Information System
• Records
• Files
• Index Cards
 Stage 1: Sequential Information Systems
• Tapes
• Files
• slow, non-interactive, redundancy,... .
 Stage 2: File Based Information Systems
• Disk (direct access)
• application program has its own file
• data redundancy
 Stage 3: DBMS based Information Systems
• Generalized data management software
• Transaction processing 10

Office automation system
• Refers to the varied computer machinery
and software used to digitally create, collect, store,
manipulate, and relay office information needed for
accomplishing basic tasks. Its objectives are:
• Paperless work environment
• Simplify operations and minimize computational errors
• Optimal utilization of resources
• Better information sharing and transparency
• Enhanced security and recovery of data
1111

Office automation system
It includes many applications such as:
 document management
 word processing
 desktop publishing
 electronic communications
 electronic scheduling
 data management
 project management
12

Document Management System
A document management system (DMS) is a computer
system (or set of computer programs) used to track and
store electronic documents and/or images of paper
documents.
Document management is a process taken with
document within an organization, with respect to the
creation, distribution and deletion of documents
13

Document Management System
benefits
1. Improve staff productivity
2. Reduce costs associated with manual document
3. Promote sharing of knowledge and information
4. Enhance corporate transparency and governance
5. E-mail and fax files instantly
6. Access documents while traveling
7. Publish documents to CD, DVD or the web, as
appropriate
14

Data, database, DBMS definition
15

16
Databases are a Rich Area for Computer Science
• Programming languages and software engineering,
• Data structures and algorithms,
• Logic, discrete maths, computation theory,
• It is a common course for students from different
department in computer and engineering science.

• Creation more databases has great
impact towards better environment of
the world, how?
17

Advantages of Using the
Database Approach
• More information from given data
• Ad hoc queries can be performed
• Redundancy can be reduced
• Inconsistency can be avoided
• Security restriction can be applied
18

Advantages of Using the Database
Approach - 2
• Sharing of data among multiple users.
• Providing backup and recovery services.
• Providing multiple interfaces to different
classes of users.
• Representing complex relationships among
data
19

What is a database?
 Database
 a collection of related records, organized into tables
 Table
 a set of data elements (values) organized by records (horizontal
rows) and fields (vertical columns)
 Record (or row)
 a single, structured data item in a table
 Field (or column)
 a set of data values of a particular simple type, one for each row
of the table
20

Database Tables: The Big Picture
To calculate the number of entries in a database--multiply the number of fields by the
number of records.
Ex. 5 fields(columns)*26 rows (records) = 130 entries in this database.
2. ENTRIES (cells)
4. RECORDS (rows)
3. FIELDS (columns)
1. Table
3. Field
2. Entries
4. Record

Comparison of Terminology
Formal (logical)relational term Informal (physical)equivalents
relation table
tuple row or record
cardinality number of rows
attribute column or field
degree
Primary key
number of columns
(unique) identifier
domain pool of legal values
22

23
What is a Database?
• It contains data specific to part of the real
world, a miniworld.
• Construction: populating tables with data.
• Manipulation: queries, updates, deletes, etc.
• It is maintained for specific applications.
23

Why do businesses use databases?
• A database is a tool used by businesses to
manage the huge amount of data required to
run the business.
– For example, a business may use several databases
to keep track of employee information, customers,
products, and prices of products.
– All of the information can be easily and efficiently
managed and shared by database software.
Slide 24

Business Rules
• What
– Brief, precise, and unambiguous descriptions of operations in an
organization
• based on policies, procedures, or principles within a specific
organization
• Why
– Enhance understanding & facilitate communication
• Standardize company’s view of data
• Constitute a communications tool between users and designers
• How (sources)
– Interviews
• Company managers
• Policy makers
• Department managers
• End users
– Written documentation
• Procedures, Standards, Operations manuals
– Observation
• Business operations
2525

What is a database tasks?
• Database tasks:
– Retrieving
– Sorting
– Summarizing
– Inserting
– Updating
– Deleting
26

Types of Databases and Database
Applications
• Numeric and Textual Databases (e.g. IRS
CADE)
• Multimedia Databases (e.g. Cortina)
• Geographic Information Systems (GIS)
• Data Warehouses
• Real-time and Active Databases
27

Examples of Databases
• Web database:
• Online library card catalog
–Media Center information
–Encyclopedias
–Dictionaries
• eBay and other online
• businesses
–Inventory
–Keep track of customers,
products, vendors, pay pal
accounts
Slide 28
► Bank accounts
► Students records
► Hospital record
► Payroll
• Stock market
• Barcode scanner keeps
• Real estate listings
• Fingerprint database

Top 5 Largest Databases in the World
• Library of Congress: 130 million items
• The Central Intelligence Agency (CIA)
• Amazon: 59 million active customers
• YouTube: 100 million videos watched per day
• ChoicePoint: Information on 250 million people
29

Database Users
• End users
– Use the database system to
achieve some goal
• Application developers
– Write software to allow end
users to interface with the
database system
• Database Administrator
(DBA)
– Designs & manages the
database system
• Database systems
programmer
– Writes the database software
itself
31

Which is better
Database System or File System?
3333

Billing
Program
Customer
file
Accounts
receivable
file
Accounts_Payable
Program
Vendor
file
Invoice
file
Sales Order Processing
Program
Customer
file
Inventory
file
Payroll
Program
Employee
file
Purchasing
Program
Buyer
file
Inventory
file
Vendor
file
File Processing Systems
34

File System: Weakness
• File system was an old system to handle data, it can be used on small scale
of data, but with larger data it become ineffective.
• Weakness
– “Islands of data” in scattered file systems.
• Problems
– Duplication
• same data may be stored in multiple files
– Inconsistency
• same data may be stored by different names in different format
– Rigidity
• requires customized programming to implement any changes
• cannot do ad-hoc queries
• Implications
– Waste of space
– Data inaccuracies
– High overhead of data manipulation and maintenance 3535

Evolution of Data Models
• A data model (or datamodel is an abstract model that organizes elements
of data and standardizes how they relate to one another and to properties of
the real world entities.
36
1960s 1970s 1980s 1990s 2000+
File-based
Hierarchical
Network
Relational
Object-oriented
Web-based
Entity-Relationship
36

Database design process
• Determine the purpose of the database - This helps
prepare for the remaining steps.
• Find and organize the information required - Gather all
of the types of information to record in the database, such as
product name and order number.
• Divide the information into tables - Divide information
items into major entities or subjects, such as Products or
Orders. Each subject then becomes a table.
• Turn information items into columns - Decide what
information needs to be stored in each table. Each item
becomes a field, and is displayed as a column in the table.
For example, an Employees table might include fields such
as Last Name and Hire Date.
40

• Specify primary keys - Choose each table’s primary key. The
primary key is a column, or a set of columns, that is used to
uniquely identify each row. An example might be Product ID or
Order ID.
• Set up the table relationships - Look at each table and decide how
the data in one table is related to the data in other tables. Add fields
to tables or create new tables to clarify the relationships, as
necessary.
• Refine the design - Analyze the design for errors. Create tables and
add a few records of sample data. Check if results come from the
tables as expected. Make adjustments to the design, as needed.
• Apply the normalization rules - Apply the data normalization rules
to see if tables are structured correctly. Make adjustments to the
tables, as needed.
41

Relational Data Structure
• Data is stored in relations (tables)
• Each relation has a scheme
(pattern) (heading)
• The scheme defines the relation’s
attributes (columns)
• Data takes the form of tuples
(rows)
Name Age
John 23
Mary 20
Mark 18
Jane 21
Attributes
Scheme
Tuples
42

Relational Data Structure
• More formally -
– A scheme is a set of
attributes
– A tuple assigns a value
to each attribute in its
scheme
– A relation is a set of
tuples with the same
scheme
{ { (Name, John), (Age, 23) },
{ (Name, Mary), (Age, 20) },
{ (Name, Mark), (Age, 18) },
{ (Name, Jane), (Age, 21) } }
Name Age
John 23
Mary 20
Mark 18
Jane 21
43

Relations
ID Name Salary Department
M139 John Smith 18,000 Marketing
M140 Mary Jones 22,000 Marketing
A368 Jane Brown 22,000 Accounts
P222 Mark Brown 24,000 Personnel
A367 David Jones 20,000 Accounts
Attributes are ID, Name, Salary, and Department Degree is 4
Cardinality is 5
Tuples, e.g.
{ (ID, A368),
(Name, Jane Brown),
(Salary, 22,000),
(Department, Accounts) }
Scheme is {ID, Name, Salary, Department}
44

A relational database management &
data model
46

A relational database management
system (RDBMS)
• A software system used to maintain relational databases is a relational
database management system (RDBMS). Virtually all relational database
systems use SQL (Structured Query Language) for querying and
maintaining the database.
• A relational database management system (RDBMS) is a database
management system (DBMS) that is based on the relational model as
invented by Edgar F.Codd, of IBM's San Jose Research Laboratory, in
1970s.
• In 2017, many of the databases in widespread use are based on
the relational database model.
• Each row in a table has its own unique key( primary key). Rows in a
table can be linked to rows in other tables by adding a column for the
unique key of the linked row
47

DBMS components
 Hardware –
the physical computer system that allows physical access to data.
 Software –
the actual program that allows users to access, maintain, and update physical
data.
 Data – stored physically on the storage devices
 Users –
 End users - Normal user and DBA (Database Administrator)
 Application programs
 Procedures –
a set of rules that should be clearly defined and followed by the users.

50
DBMS Functions
• Data dictionary management
• Data storage management
• Data transformation and presentation
• Security management
• Multiuser access control
• Backup and recovery management
• Data integrity management
• Database language and
• application programming interfaces
• Database communication interfaces

51
DBMS functions
51
DBMS engine

52
The Database for a small company
52

The leading vendors (sellers) of RDBMS
• There 10s 0f RDBMS vendors the leading ones are:
**** RDBMS Vendors **** RDBMS Product ****
Computer Associates INGRES
IBM DB2
INFORMIX Software INFORMIX
Oracle Corporation Oracle
Microsoft Corporation MS Access
Microsoft Corporation SQL Server
MySQL AB MySQL
NCR Teradata
PostgreSQL Dvlp Grp PostgreSQL
Sybase Sybase 11
53

RDBMS vendor market share
54
In 2016 the revenue reached 35 billion dollars for the Oracle.

Which relational DBMS is best for your company?
• If you're a large organization with a mainframe and want
• For Unix and Linux installations, your primary choices are
Oracle and DB2.
• Oracle is the market leader on those platforms, though IBM
has a solid presence there, too.
• For Windows development, Microsoft is the clear leader on
its own OS. Also, , Microsoft has announced plans to
support SQL Server on Linux.
55

Database design
• Database design is the process of producing a
detailed data model of database.
• This data model contains all the needed logical
and physical design choices and physical storage
parameters needed to generate a design in a data
definition language, which can then be used to
create a database.
• A fully attributed data model contains detailed
attributes for each entity.

57
DBMS STANDARDIZATION
ANSI ARCHITECTURE

ER model -- Database Modeling
 Database designs include ER (entity-relationship
model) diagrams. An ER diagram is a diagram that
helps to design databases in an efficient way.
 The ER data model employs three basic concepts:
 entity sets,
 relationship sets,
 attributes.
 The ER model can express the overall logical structure
of a database graphically.
58

Basics of E-R Diagrams
• Entity
– represented by a rectangle
with its name in capital
letters.
• Relationships
– represented by an active or
passive verb inside the
diamond that connects the
related entities.
• Connectivities
– i.e., types of relationship
– written next to each entity
box. 5959

60
Schemas
• Relation schema = relation name and attribute
list.
 Optionally: types of attributes.
 Example: Beers(name, manf) or Beers(name: string,
manf: string)
• Database = collection of relations.
• Database schema = set of all relation schemas in
the database.
60

COMPANY
Database
Schema
62

Example of a Relation
STUDENT (Name, SSN, Home_phone, Addr, Office_phone, Age, GPA)
63

64
Example: University Database using
E/R diagram
• Professors work for only one department
• Departments have many professors
• Each course is taught by only one professor
• Students make a plan or program of study
• A course could meet in several rooms/times
• Graduate students must have an advisor
• Cities are categorized as resident/BirthPlace
• Visiting prof. need an End/Start date

65
E/R diagram of a University Database
BIRTH_PLACE
CITY
Name
State
PERSON
LastName
Age
PROFESSOR
TenureStatus
Title
STUDENT
DEPARTMENT
Name
Phone
Belongs_To
ENROLLED
Semester
Grade
PLANNED
Semester
GRADUATE_STUDENT ADVISED_BY
VISITING_
PROFESSOR
Start_Appointment
End_Appointment
COURSE
Title
Description
Credits
TAUGHT_BY
Semester
MEETS
ROOM
RoomNumber
Building
TIME
Day
Hour
RESIDENT
1 N
N
N
N
N
N
N
1
N N
N 1
1
N
N
1

Types of Data
1. User data
2. Metadata
3. Indexes
4. Application Metadata
66

1. User Data
• A table of data is called a relation
• Columns are fields or attributes
• Rows are specific instances
• Relations must be structured properly
67

2. Metadata or
Data Dictionary
“a description of the structure of the database”
System tables store metadata, including:
 table names
 field names
 primary key fields
 data types
 field size
 data constraints (e.g., input masks, and validation rules)
 relationships between tables
68

4. Application Metadata
Stores the structure and format of:
– forms
– reports
– Queries:a query is a form of questioning using query language
– other application components
71

Relations Keys
“In rational database the relations are connects through unique
identifier called key. It is a group of one or more attributes
that uniquely identifies a row”

Types of Keys
• A (primary) key is one (or more) columns
of a relation that is (are) used to identify a
row
• A composite key is a key that contains two
or more attributes
– For a key to be unique, it is sometimes necessary to use a
composite key
– Can also generate a set of unique values to serve as the
key (for example University ID numbers)
73

A Foreign Key
• A table may be related to other tables (i.e., a
relationship)
• To create relationships, you may need to
create a foreign key
• A foreign key is a primary key from one table
placed into another table
• Referential integrity - every value of a foreign
key must match a value of an existing primary
key
75

Properties of a Relation (table)
1. There are no duplicate tuples (rows).
–The body of the relation is a
mathematical set (i.e., a set of tuples),
and sets in mathematics by definition do
not include duplicate elements.
–If a "relation" contains duplicate tuples,
then it is not a relation.
77

Properties of a Relation
2. Tuples (rows) are unordered (top to bottom).
– Sets in mathematics are not ordered. So,
even if a relation A's tuples are reversely
ordered, it is still the same relation.
– Thus, there is no such thing as "the 5th
tuple" or the last tuple. In other words,
there is no concept of positional
addressing.
78

3. Attributes (columns) are unordered (left to right).
–The heading of a relation is also defined
as a set.
–There is no such thing as "5th attribute
(column)" or the last attribute.
79

4. All attribute values are atomic.
– At every row-and-column position within
the table, there always exists precisely one
value, never a list of values. Or
equivalently, relations do not contain
repeating groups.
– A relation satisfying this condition is said to
be in First Normal Form.
80

Entity Integrity Rule
• Guarantees that each entity will have a unique
identity and ensures that foreign key values can
properly reference primary key values.
• Requirement
– No component of the primary key is allowed
to accept nulls.
– By "null" here, we mean that information is
missing for some reason.
81

Foreign Key
• An attribute in one table whose values must either match
the primary key in another table or be null.
• Attribute FK of base relation R2 is a foreign key if and
only if it satisfies the following two time-
• independent properties:
– Each value of FK is either wholly null or wholly non-
null.
– Each non-null value of FK is identical to the value of
PK in some tuple of R1.
82

Referential Integrity Enforcement
• Referential Integrity (RI) is a database concept used to ensure that the
relationships between your database tables remains synchronized during
data modifications, you may choose among those items:
• Restriction:
– does not allow any deletion
• Nullification:
– if value is deleted, reference value will set to be null.
• Cascading:
– if value is deleted, reference value will also be deleted.
– if value is updated, reference value will also be updated.
• Default value:
– if value is deleted, reference value will be have default value, which is
provided by the system.
83

Referential Integrity Enforcement
• Cascade Update Related Fields
– Change of PK values in primary table 
automatic change of FK values
• Cascade Delete Related Fields
– Delete of a record in the primary table 
automatic delete of all records in the related
table that have a matching FK value
84

Data Definition Language (DDL)
• : DDL is used for specifying the database schema. Let’s take
SQL for instance to categorize the statements that comes
under DDL.
• To create the database instance – CREATE
• To alter the structure of database – ALTER
• To drop database instances – DROP
• To delete tables in a database instance – TRUNCATE
• To rename database instances – RENAME
• All these commands specify or update the database schema
that’s why they come under Data Definition language.
87

Data Manipulation Language
(DML)
• DML is used for accessing and manipulating
data in a database
• To read records from table(s) – SELECT
• To insert record(s) into the table(s) – INSERT
• Update the data in table(s) – UPDATE
• Delete all the records from the table –
DELETE
88

Data Control language (DCL)
• DCL is used for granting and revoking user access
on a database –
• To grant access to user – GRANT
• To revoke access from user – REVOKE
• In practical data definition language, data
manipulation language and data control languages
are not separate language; rather they are the parts
of a single database language such as SQL.
89

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