Database and DBMS

Why?

• Databases can be considered as electronicfiling systems.

• Computing power and amount of data isincreasing.

• How do you convert all that data to usefulinformation, tailored to your needs.

Data vs information

Data+

Structure=

Information

Miniworld

• A database represents some aspect of thereal world, sometimes referred toas miniworld.

• Changes in the miniworld are reflected inthe database.

Simple Data.

• Simple Data → Simple Information.• E.G. Dates of Birth of your family members.– Such information can be stored in memory.• Dates of Birth of your family, friends, co-workers.– Can be stored on a piece of paper or flat text files.• The Data here is simple, and information providedis straight forward, there is no need for a complexdatabase.

Complex Data.

Information on Gene X.• Protein• Species• Polymorphisms• More Proteins• Attributes

Flat File Approach

• Data can still be stored in flat files.• May even work for single/small number of users.• Consistency issues.

– No apparent relationships between different files/data.– No fixed protocols for data access.– Data integrity & duplication.

• Data structure is rigid – makes it difficult tochange or update.

Definition of Database.

• A shared collection of logically related data(and a description of this data) designed tomeet the information needs of an

organisation.– Data is shared.– Collection.– Logically related (Entity relationship model –

ER).

Real World Applications

• Applications in the real world are usually rich inconcepts and there are various associations among these concepts.

• University Academic System– Courses– Faculty Allocated– Classes– Students– Schedule

• Association between these concepts.

Terminology

• Entity: an object or a concept from the real world• Entity set: a collection of entities• Attribute: a property of an entity• Relation: a “table” with columns and rows• Tuple: a row in a table• Relationship: an association between two or more

entities• Database: a set of tables for entity sets and relationships• Rel. Database: a collection of normalized tables

Primary and Foreign Keys

• The primary key is the candidate key that isselected to identify entities uniquely within the relation

• A foreign key is an attribute or a set of attributes that matches the candidate key of some relation.

Some Biological Databases1. DDBJ (DNA Data Bank of Japan)2. EMBL Nucleotide DB (European Molecular Biology Laboratory)3. GenBank (National Center for Biotechnology Information)4. UniProtKB (Universal Protein Resource Knowledgebase)5. Swiss-Prot Protein Knowledgebase (Swiss Institute of Bioinformatics)6. PROSITE Database of Protein Families and Domains7. Protein Data Bank (PDB) (Research Collaboratory for StructuralBioinformatics (RCSB))

Ref:http://en.wikipedia.org/wiki/Biological_database#Example_public_databases_for_molecular_biology and look through various database examples.

Problem 1

• A program is required to prompt the terminal operator for the maximum and minimum temperature readings on a particular day, accept those readings as integers, and calculate and display to the screen the average temperature, calculated by (maximum temperature + minimum temperature)/2.

• Defining diagram

Input Processing OutputMax_tempMin_temp

Prompt for temperaturesGet temperaturesCalculate average temperatureDisplay average temperature

Avg_temp

Solution Pseudocode

Begin programPrint Get inputs #command for prompt

Get max_temp, min_temp #command for inputs

avg_temp= (max_Temp + min_temp)/2 # command for airthmetic process

Print Output avg_temp #command for

output End Program

Max_temp Min_temp Avg-temp

52 25 X

Problem 2

• Calculate the circumference and area of a circle

• Defining diagram

Input Processing OutputRadiuspi

Get radius, piCalculate circumference = 2 * P I* radiusCalculate area=PI * radius ^ 2Display circumference, area

Circumference

area

Solution PseudocodeBegin program

get radius, PI circumference = 2 * P I* radius

area=PI * radius * radiusdisplay circumference, area

End program

radius pi cumference = 2 * P I* radius

area=PI * radius * radius

5 3 2*3*5=30 3*5*5=75

Problem 3

• an increment program with increment of 3, max=10, min=1

• Defining diagram

Input Processing Outputimaximinincrement value

Get imax, Imin, increment value

Run for loop max times using increment operator

Display values for increment

imin

Solution PseudocodeBegin program

for ( i=1; i<=10; i+3) display i

i+3End program

i (display) i=i+3 Condition check(i<=10)

1 1+3=3 3<=10 Y

3 3+3=6 6<=10 Y

6 6+3=9 9<=10 Y

9 9+3=12 12<=10 N

Problem 4

• a decrement fire program with user given values for increment, max, & min operator

• Defining diagramInput Processing Output

imaximindecrement value

Prompt for input of imax, Imin, decrement value

Get imax, Imin, decrement value

Run for loop max times using decrement operator

Display values for decrement

Display „FIRE“.

imax

Solution PseudocodeBegin programPrint “Take value of” i, x, y

for ( i; i>=x; i-y) display i

i-yPrint “FIRE”End program

(output)i=10

i-yWhere y=1

Condition check(i>=5)

10 10-1=9 9>=5 Y

9 10+1=8 8>=5 Y

8 10+1=7 7>=5 Y

7 10+1=6 6>=5 Y

6 10+1=5 5>=5 Y

5 10+1=4 4>=5 N

FIRE

Problem 5

• Given a user value tell the integer status in terms of being positive or negative

• Defining diagram

Input Processing OutputX Prompt for input of x

Getx

If (x<0) diaplay „user entered a negative integer“ Elseif (x>0) diaplay „user entered a positive integer“ Else display „user has entered a zero“

Assesment

Solution PseudocodeBegin program

Print “Take value of” xGet x

If (x<0)diaplay “user entered a negative integer”

Elseif (x>0)

diaplay ”user entered a positive integer” Elseif(x==0)

display “user has entered a zero“

End program

x Condition

check(x<0)

Condition

check(x>0)

Condition

check(x=0)

Output

10 10<0N

10>0 Y

Not checked

user entered a positive integer”

GOOD LUCK