NORMALIZATION

NORMALIZATION




First Normal Form (1NF)
First normal form (1NF) sets the very basic rules for an organized database. A normal form used in database normalization. A relational database table that adheres to 1NF is one that meets a certain minimum set of criteria. These criteria are basically concerned with ensuring that the table is a faithful representation of a relation and that it is free of repeating groups.



Second Normal Form (2NF)
Second normal form (2NF) further addresses the concept of removing duplicative data:
• Meet all the requirements of the first normal form.
• Remove subsets of data that apply to multiple rows of a table and place them in separate tables.
• Create relationships between these new tables and their predecessors through the use of foreign key( a field in a relational table that matches the primary key column of another table. The foreign key can be used to cross-reference tables)


Third Normal Form (3NF)
Third normal form (3NF) goes one large step further:
• Meet all the requirements of the second normal form.
• Remove columns that are not dependent upon the primary key.

Normalization

Normalization
1. Gathering requirement user or business
2. Developing E-R Model pursuant to requirement user or business
3. Convert E-R model to the set of relations (tables)
4. Relationship normalization to eliminated or removed anomaly
5. Implemented to create a database with a table for each relationship that is normalization

DATABASE NORMALIZATION
1. Normalization is process basis structure forming data so a considerable part ambiguity can be removed
2. Normalization phase is begun of lightest phase (1NF) until tightest (5NF)
3. Just usually comes up 3NF zoom or BCNF because was enough is equal to result qualified table well

Why do normalization?
a. Optimizing table structures
b. Increase speed
c. The income data is the same
d. More efficient in the use of storage media
e. Reduce redundancy
f. Avoid anomalies (insertion anomalies, deletion anomalies, update anomalies)
g. Improved data integrity

One table is said well (efficient) or normal if pock 3 criterions as follows:
a. If there is decomposition table, therefore decomposition it shall be secured safe( Lossless Join Decomposition ). Its mean, after that table is untied or at decomposition becomes new tables, that new tables can result tables originally equally a hair breadth
b. It's petted dependable functional at the moment data change (Dependency Preservation)
c. Don't breach Boyce Code Form Normal (BCNF)

If the third criterion (BCNF) can't be accomplished, therefore at least that table not breach the third phase Normal Form (3rd is Normal Form or 3NF)

Functional Dependency
1. Functional Dependency describe the attributes relationship in a relationship
2. An attribute said functionally dependant on the other, if we use the value attribute to determine the value of the other attributes
3. The symbol that is used to represent --> functional dependency.
--> reads determine the functional
Notation: A --> B
A and B is attribute of one table. Matter functionally A determines B or B cling to A, if and only if available 2 data row with appreciative A same, therefore point B also same.
Notation: A -/-> B or A x -->B
Are opposite of previous notation
Example




Functional Dependency:
a. NRP --> Name
b. Mata_Kuliah, NRP --> Value
Non Functional Dependency:
a. Mata_Kuliah --> NRP
b. NRP --> Value
FIRST NORMAL FORM (First is Normal Form - 1NF)
A table is said exist on normal form I if it don't exist on form un normalized table, where is happening multiplexing a sort field and enabling available field that null (empty).
Be not been allowed marks sense:
• Attribute that valuably there are many ( Multi valued attribute ).
• Attribute composite or combine of both.
So:
• domain price attribute shall constitute atomic price
SECOND NORMAL FORM (second is Normal Form 2NF)
2NF normal form is accomplished in one table if have accomplished 1NF form, and all attribute besides primary key, as whole to have Functional Dependency on primary key. One table not accomplishes 2NF, if there is attribute which its dependency (Functional Dependency) just gets partial character only (just depend to one part of primary key.) If anything attribute that have no dependency for primary key, therefore that attribute has at move or is removed. Functional dependency x --> Y. is said heaving full if erases A attribute of x matter y. no longer functional dependent. Functional dependency x --> Y. is said partial if erases A attribute of x matter y. still functional dependent. Relationship scheme r deep shaped 2NF if each attribute non primary key A Î R full dependent functionally on primary key R
Third Normal Form - 3NF
The form of normal 3NF has been met if the form meets 2NF, and if there are no non-primary key attribute that has a dependence on non-primary key attributes of the other (transitive dependencies)

Database & Entity Relationship Diagram

Database & Entity Relationship Diagram

Definition Of Database

1. A group of data which stored in magnetic disk, optical disk or other secondary storage

2. A group of data which is linked one to other of an enterprise(factory, governmental institution, or private section)

Database Management System

1. Collection a database with software application in based of database

2. This software application is use for accessing and maintaining the database

3. The first aim of DBMS is to preparing an easy and efficient environment for using, collecting, and storing data and information

BIT, BYTE, FIELD

1. Bit : Is the smaller part of data, which contain of value 1 or 0

2. Byte : A group of same kind of bit

3. Field : A group of same kind of byte, which in database is called attribute

Attribute / Field

1. Is a characteristic from entity, which preparing detailed explanation about that entity

2. A relationship also can have attribute

Types Attribute

1. Single versus Multi value

a. Single is only can fill at most one value

b. Multi value is can fill with interest from one value with same type

2. Atomic versus Composition

a. Atomic is indiscrete into smaller attribute

b. composition is representing aliance from some smaller attribute

3. Derived attribute

Attribute which its value can be yielded from other attribute value

4. Null value attribute

Attribute which do not have value to a record

5. Mandatory value attribute

Attribute which must have value

Record / Tuple

1. Representing an data line in a relationship

2. Consist of attributes corps where attributes of interaction to inform entity / relationship completely

Entity / File

1. File represent corps of record which of a kind and have is same element, same attribute but different each other its data of him

Type file:

In application process, file can be categorized likes:

a. File Mains

b. File Transaction

c. File Report

d. File History

e. File Protector

f. File Work

Domain

Domain represent corps of values which enabled to stay in one or more attribute. Every attribute in a relational database is defined like a domain

Key Element Data

Key is element of record which used to find the record when accessing or can also used to identify every entity / record / row

Types Key

1. Super key

Super key is one or more attribute from a table which can be used for identifying entity / record from table uniquely

2. Candidate key

Candidate key is super key with minimum attribute. Candidate key may not contain attribute of other table so that the candidate is super key, but not the contrary

3. Primary key

One of the attribute of candidate key can be selected / determined into primary key with 3 criteria:

a. The key is more natural for use as reference

b. The key is more simple

c. The key is unique

4. Alternate key

Alternate key is attribute of candidate key which is not chosen become primary key

5. Foreign key

Foreign key is any attribute subjecting to primary key at other tables. Foreign key will be happen in a relation which have one too many cardinality or many to many cardinality. Foreign key usually put at the table which direct to many cardinality

6. External key

External key is lexical attribute or collection of lexical attribute which values always identify one object instance

ERD (Entity Relationship Diagram)

ERD is a model of a network that uses word order is stored in the system of abstract

The different between DFD and ERD

a. DFD is a model of network functions that will be implemented by the system

b. ERD is a model that emphasizes the network data on the structure and relationship data

Degree Relationship

1. Unary relationship

Is the relationship model between the entity originating from the same entity set

2. Binary relationship

Is the relationship model between two of entities

3. Ternary relationship

Is a relationship between the instance of three types of entities are unilateral

Cardinality

1. One to one

Level one to one relationship with the one stated in the entity's first event, only had one relationship with one incident in which the two entities and vice versa

2. One to many or many to one

Level one to many relationship is the same as the one to many depending on the direction from which the relationship have to seen. For an incident on the first entity can have many relationships with the incident on the second entity, if the one incident in which two entities can only have a relationship with one incident on the first entity

3. Many to many

If any incident occurs in an entity has many relationships with other entities in the incident

Example of cardinality

DFD Quiz

Data Flow Diagram

Data Flow Diagram (DFD)
1. Depicting the division of system into smaller module
2. Facilitating user for to understand system to be done

Context Diagram
1. Consist of a process and depict scope from a system
2. Representing highest level of DFD depicting all system to input and output of the system
3. System is limited by boundary (depicted by dash line)
4. There is no storage

Zero Diagram
1. Depicting process of DFD
2. Opening regarding on by totally handled of system, showing existing especial process or function, data flow and external entity
3. At this level is enabled the existence of data storage
4. For process which not detailed again at level hereinafter hence enhanced symbol ‘*’ or ‘ P’ by the end of process number
5. Input and output balance between zero diagram context, diagram should be maintained

Detailed Diagram
Is a diagram that interpret what is the process in the diagram zero level or above
Numbering level at DFD:




In one level there should be less than 7 units and the maximum of 9, when more should be done in the disintegration

Specification Process
1. Each process in DFD must have the specification of process
2. At top level method used to depict process earn by using descriptive sentence
3. At more level detailed that is most under process (primitive functional) requiring the more of structure specification
4. Specification of process will become guidance to programmer in making program (coding)
5. Method which used in specification of process: breakdown of process in the form of story, decision table, tree decision

External Entity
1. Something that beyond system, but he give data into system or give data of system
2. Symbol with box notation
3. External entity not be including the part of system
4. Naming:
a. The name of terminal in the form of noun
b. Terminal may not have the name same except its same object is true

Data Flow
1. Data flow is Representing place emit a stream of information
2. Depicted with connective straight line component of system
3. Data current shown with direction bow and line called of data current emit of a stream
4. Data current emit a stream of among process, data of storage and show data current of data which in the form of input for system

Guidelines of the name:
1. Name of the flow of data that consists of some words associated with the flow lines connect
2. No flow data for the same and the name should reflect its content
3. The flow of data that consists of several elements can be expressed with the group element
4. Avoid using the word 'data' and 'information' to give a name to the flow of data
5. Wherever possible the complete flow of data is written

Other provisions:
1. Name of the flow of data into a process may not be the same as the name of the data flow out of the process
2. Data flow into or out of data storage doesn’t need to be given a name if:
a. The flow of data simple and easy to understand
b. Describes the data flow of all data items
3. There can be no flow of data from the terminal to the data storage, or vice versa because the terminal is not part of the system, the relationship with the terminal data storage must be through a process

Process
1. The process is what is done by the system
2. The process can process data flows or data entry into the flow of data out
3. The transform function of one or more of data input into one or more of the output data in accordance with the desired specifications
4. Each process has one or more inputs and produce one or more output
5. The process is also often called bubble

Guidelines of the process:
1. Name of the process consists of a verb and noun, which reflects the function of the process
2. Do not use the process as part of the name of a bubble
3. May not have some process that has the same name
4. The process should be given a number. Order number wherever possible to follow the flow of the process or sequence, but the sequence number does not mean that the absolute is a process in chronological order

Data Storage
1. Data Storage represent existing data repository in system
2. Symbol with a couple of parallel line or two line wrongly one side from other side openly
3. Process can take data from or give data to database
4. Guidance giving of name:
a. Name have to express data of storage
b. If its name more than one word hence have to say the word to joint

DFD Symbols



Data Dictionary
1. Work to help the system to interpret the application in detail and organize all elements of the data used in the system precisely so that the system analyst and have a basic understanding of the same input, output, storage and processing
2. At analysis, the data dictionary is used as a means of communication between the systems analyst with the user
3. At the system design, data dictionary is used to design input, reports and databases
4. Flow data on the global DAD, further details can be seen in the data dictionary

Restrictions in DFD
1. Data flow not be outside of the entity directly to the other outside entities without going through a process
2. Data flow not be directly from the data store to entities outside without going through a process
3. The data flow not store data directly from the data store without the other through a process
4. Data flow from one process directly to the other without going through the process of a data store should / be avoided as much as possible

fourth quiz

FIRST OBSERVATION AND ANALYSIS REQUIREMENT

Concept Investigation System

1. Discrepancy difference between target condition system and fact in system

2. The report of detection problem is not real

a. Purpose very ideal

b. Not enough resource and or attitude

c. System measurement not accurate

d. System purpose are very old

e. Difference between idle system and temporary system

3. Problem solving

a. System Formulation which walking

b. Getting ideal consensus system

c. Developing some alternative

d. Chose the best alternative

4. Investigation purpose

Constraint In Investigation System

When doing the investigation of some constraint which often emerge is

1. Time

2. Cost

3. Science

4. Politic

5. Interference

Recommendation

Result of investigation is a recommendation which is filled with:

1. Do not take action anything

2. Doing conservation system

3. Increase ability or skill of user

4. Totally consider to system modification

5. Placing problem into development system plan

Investigation Tactic

Why need tactics?

1. Finding all problem

2. Knowing appearance cause of problem

3. Determining correct solution

Some tactics to be able

1. Listening opinion from perpetrator system

2. Don’t give first resolving

3. Comparing story some people from perpetrator system about same case

4. Attention the logical inconsistent problem

Investigation Technique

Direct:

1. Questioner

2. Question and Answer

3. Observation

Non-direct:

1. Current procedure

2. Studying the document

3. Sample

4. Tabular

Description System In This Time

1. Input

2. Output

3. File

4. Data element

5. Transaction volume and action document

6. Data flow chart

Analysis Requirement

4 purposing wish to be reached:

1. Explaining system completely

2. Depicting ideal information system

3. Bringing ideal information system to condition in this time by paying attention resource constraint

4. Giving motivation to confidence of [user/ wearer] into system development

Method:

1. Question and Answer

2. Questioner

3. Observation

4. Analysis Procedure

5. Document observation

Resource constraint

1. Time

2. Cost

3. Skill

4. Technology

5. External factor

Document analysis requirement

1. Analysis direction: relationship with the end user, process monitoring, problems in data gathering.

2. User needs: real needs, report needs, exercise needs, and new system influence.

3. System constraint: explain time and cost constraint, skill, technology and external factor.

4. Document kind data gathering instrument, statistic consensus, data flow according to physic and logical, first data element in data dictionary.

Generating Systems Alternatives

How to draw near the system condition in this time with the ideal condition system?

1. Making alternative to solve problem information system

2. The best alternative applied wisely

Choice Strategy

1. Distributed Versus centralized processing

Change decision of information centralized data processing to center responsibility user end decentralized

2. Integrated Versus dispersed database

Designer of system have to consider data any kind of which enter in data base and which come into File

3. Surround Strategy of System Development

Environmental about important strategy in the case of confiscation because information system of other company possible differ from company in this time

Choice tactic

Do before operational planner selection started

Operational planner selection

Planner selection is able categorize into:

1. Input

a. Online Vs Off Line Data Entry

b. Keyed Vs Machine Readable Data Entry

c. Centralized Vs Decentralized Data Entry

2. Processing

a. Batch Vs Real-time record update

b. Sequential Vs Direct Access to records

c. Single Vs Multiple User update of records

3. Output

a. Traditional Vs Turn Around Documents

b. Structured Vs Inquiry based reports

Selecting The Proper System

There is 3 system of A told by more pre-eminent with other system if

1. A have lower expense of B and advantage both is same

2. A have lower expense of B and of A yield advantage which more than B

3. A and of B have same expense but yielded by advantage A more

Some comparative Method System

1. Break Even point Analyisis

2. Payback Period

3. Discounted PayBack period

4. Internal Rate of Return

Cost category

1. Hardware

2. Software

3. People

4. Suppliers

5. Telecommunications

6. Physical sites

Cost details

Comparing system information the expense of life system, projection analyst how many change of expense for the future and there is 3 model of expense information system that is Linear, Exponential and Step Function

Information system cost happen in one time and be able happen continuous

1. Information system cost happening in one time that is on-time cost and development cost while system development consist

2. Information system cost happening continuous there are recurring cost with operational cost while cost happen at information system operated every day

Factor Information System

Qualitative factor direct to best information system there are:

1. Lessening mistake storey

2. Lessening time to repair mistake

3. Lessening time listen carefully from alternative workstation

4. Quickening ready time information

5. Improving system security

6. Multiply update of source of active record

7. Improving satisfaction of user

Factor Strategy Company

1. Satisfaction of consumer

2. Mount sale mount

3. commitment Consumer and vendor

4. Information product marketing

Presenting Study System

1. Doing presentation in a word

2. Lessening clarification of technique detail

3. represented clearly with visual tool

4. If using model use appliance assist for example laptop so that more informative

5. Emphasizing advantage of information system proposal with a few existing alternative according to condition of natural company

Decision Continue Or Not

1. If company set mind on to develop system hence information department will process hereinafter that is Process of Design System

2. If on the contrary hence System Development Life Cycle ( SDLC) will be discontinued

3. Frequently will be found the problem of with study system and and usually management top will ask of reworking to study system

4. Model will explain repeated step some part and sometime information department will make decision to repeat step before explaining study system

5. With alternative, decision to repeat a step of SDLC not to speak of or previous Go – No – Go Decision.