juliarta

Normalization: An Exercise

2009-05-03T04:23:00.000-07:00

In this time, I have given a description of ERD in subjects ADSI. But I see some gaffe in ERD . Here is the ERD :

from the picture above, we can see 2 awkwardness that is:
1. no cardinality between PART and PROJECT
2. Ternary relation between TANGGUNGAN and PROJECT
On the ERD that can be changed according to the business process logic. I ERD can be improved as below:

I add 1-N cardinality in relationships and PROJECT and BAGIAN because:
- 1 BAGIAN can handle a lot of PROJECT and,
- Many PROJECT can be handled by 1 BAGIAN
The goal of fix ERD is doing so at the mapping tables from ERD, the results from the mapping table as much as possible into the form of 2NF or 3NF if the mapping is done correctly.
Therefore, it is then there are rules that I use during the mapping. Rules are:
1. If the relation 1-N in the primary key (1) move to (N) and vice versa applies.
2. If the relationship M-N will be created a new table with the primary key of each entity will be became the primary key in the new table.
3. If the relationship 1-1 then choose higher cardinality to put primary key for a foreign key in relation table .
4. If the dependent relationships of the primary key table dependent primay key derived from the mother entity.
So from that rules, i struggle to mapping that ERD, here isi the tables :

Fro that mapping above, we can see that tables created from mapping have meet 3NF normalization. Because the relation should not have a non key attribute functionally determined by another non key attribute ( or by a set of non key attributes). That is, there should be no transitive dependency of a non key primary key.

Database Normalizatio

2009-04-26T05:12:00.000-07:00

• Process the Database Device
Collect the requirement user / business, Develop the E-R Model pursuant to requirement user business and Convert the E-R Model to relationship gathering tables of relationship Normalization to eliminate the anomaly Implementation to database by making table to each relationship normalization.

• Normalization of Data Bases
Normalization is process of forming of structure of data bases so that most ambiguity can be eliminated. of Normalization Phase started from lightest phase ( 1NF) tightest till ( 5NF) and Usually only come up with the storey level 3NF or BCNF [of] because have adequate enough to yield the tables which good with quality.

Is why [done/conducted] [by] normalization ?
 Optimalization structure of[is tables of
 Improve the speed
 Eliminate the same data inclusion
 More efficient in storage media use
 Lessen the redundancy
 Avoid the anomaly ( insertion anomalies, deletion anomalies, update the anomalies).
 improved o data Integrity.

A tables told by goodness ( efficient) or normal if fulfilling 3 criterion such as:
 If there is decomposes of tables of, hence decomposes have to be secured ( Lossless-Join Decomposition). Its Meaning, after the tables elaborated / decomposes become the new tables, the new tables can yield the tables from the beginning with of equal precisely.
 Looking after of functional depending at the time of data change ( Dependency Preservation).
 Do not impinge the Normal Boyce-Code of Form ( BCNF)
of If third criterion ( BCNF) cannot be full filed, hence at least the tables do not impinge the Normal Form of third phase ( 3rd Normal of Form / 3NF).

Functional Dependency
- Functional Dependency depict the relation attributes in a relationship
- of An attribute told by functionally dependant of other if we use the attribute value to determine the other attribute value.
- Symbol used is to deputize the functional dependency.

read functionally determine the
- Notation: A > B
A And B is attribute from a tables. Mean functionally A determine the B or B of depend on A, if and only if there is 2 data line with the same value A, hence assess the B also is of equal
- Notation: A B or A x B

Functional Dependency:
- NRP > Name
- Mata_Kuliah, NRP > Assess

Non Functional Dependency:
- Mata_Kuliah > NRP
- NRP Assess the
- Functional Dependency from tables of value - Nrp Name

Because to every same value Nrp, hence assess the Name also of equal
- { Mata_Kuliah, NRP} Assess
Because attribute Assess depend on Mata_Kuliah and NRP by together. In other ;dissimilar meaning for the Mata_Kuliah of same and NRP, hence Assess also is of equal, because Mata_Kuliah and NRP represent the key ( having the character of unique )
- Mata_Kuliah NRP
- NRP Assess

SECOND NORMAL FORM ( Normal Second of Form - 2NF)
- normal Form 2NF full filed in a tables if have fulfilled the form 1NF, and all attribute of besides primary key, intactly own the Functional Dependency at primary key
- A tables [do] not fulfill 2NF, if there is attribute which its depending ( Functional Dependency) only have the character of the just partial ( only depend on some of primary key
- If there are attribute which do not own the depending to primary key, hence the attribute have to be moved or eliminated functional o Depending of X ,Y told by full if vanishing an attribute A from X mean the Y shall no longer hinge functional.
- functional Depending of X, Y told by partial if vanishing an attribute A from X mean the Y still hinge functional.
- of Scheme of relationship R in the form of 2NF if every attribute of is non primary key A R hinge full by fungsioanal at primary key R.

NORMAL FORM THIRD ( Normal Third of Form - 3NF)
normal o Form 3NF full filed by if have fulfilled the form 2NF, and otherwise there is attribute is non primary key owning depending to attribute is non primary key the other depending transitive.

Normal Boyce-Code of Form ( BNCF)
Normal Boyce-Code of Form have the constraint which is stronger than Normal form third. To become the BNCF, relationship have to in the form of Normal of first and every attribute forced to base on the function at super attribute of key.
At example of hereunder there are Seminar relationship, Lock the Primary is NPM + Seminar . Student may take one or two seminar. Every seminar require 2 counselor and every student guided by one of among 2 the seminar counselor. Every counselor only may take one just seminar. at this example of NPM And Seminar show a Counselor.

ER Diagram quiz

2009-04-19T05:54:00.000-07:00

DEFINITION Database
Definition of the database:
A set of data stored in the magnetic disk, optical disk or other secondary storage
Collection of integrated data-related data of an enterprise (company, government or private)
À companies manufacturing : production planning data, actual production data, data ordering materials, etc.
À hospital : patient data, doctor, nurse, etc.
DATABASE MANAGEMENT SYSTEM
Collection / database combined with software applications that are based database
Application programs are used to access and maintain databases
The main purpose DBMS is to provide an environment that is efficient and easy to use, withdrawal and storage of data and information
DATABASE MANAGEMENT SYSTEM
Collection / database combined with software applications that are based database
Application programs are used to access and maintain databases
The main purpose DBMS is to provide an environment that is efficient and easy to use, withdrawal and storage of data and information
BIT, BYTE, Field
À part is a bit of data which contains the smallest value of 0 or 1
Byte à-bit set of bit similar
Field à-byte set of bytes is similar, in the database used the term attribute
NIM NAME ADDRESS
9455500001 Abdullah objects RAYA NO 4
Aminah CILEDUG 9455500002 CENTRAL NO 4
9455500003 Budiman Halimun NO 7
Attribute / Field
It is the nature or characteristics of an entity that provides provide detail on these entities
A relationship can also have attributes
Example attributes:
STUDENTS: NIM, NAME, ADDRESS
CAR: NOMOR_PLAT, COLOR, TYPE, CC
TYPE-TYPE Attribute
Single vs. multi value
Single à can only be filled at most one value
À Multi value can be filled with more than one value with the same type of
Atomic vs. composition
Atomic à can not be divided into the attributes of smaller
À composition is a combination of several attributes of a smaller
TYPE-TYPE attribute (2)
Derived attribute
attribute value can be derived from the value of other attributes, e.g. age à attributes resulting from the date of birth
Null Value attribute
Attributes that have no value to a record
Mandatory attribute Value
Attributes must have values
RECORD / TUPLE
It is a line of data in a relationship
Consists of the set of attributes where the attribute-attribute-attribute is to inform each other entity / relationship fully
Entity / FILE
File is a collection of similar records and have the same elements, the same attributes but different data value.
File Type
In processing applications, files can be classified. as follows:
- Master File
- Transaction Files
- File Reports
- File History
- File Protection
- File Work
DOMAIN
Domain is the set of values that are allowed to reside in one or more attributes. Each attribute in a database relation is defined as a domain
Element KEY DATA
Key elements of record which is used to find these records at the time of access, or can also be used to identify each entity / record / line.
SPECIES OF KEY
Super key is one or more attributes of a table that can be used to identify entity / record of the table are unique (not all attributes can be super key)
Cadidate Key is a super key with minimal attributes. Candidate must not contain a key attribute of the table so that the other candidate key is certain super key but not necessarily vice versa.
Primary Key
One of the key attributes of the candidate can be selected / specified a primary key with the three following criteria:
1. Key is more natural to use as reference
2. Key is more simple
3. Key is guaranteed the uniquely.
SPECIES OF KEY (2)
Alternate Key is an attribute of the candidate key is not selected to be primary key.
Foreign Key is any attribute that points to the primary key in another table. Foreign key will be going on a relationship that has cardinalities one to many (one to many) or many to many (many to many). Foreign key is usually always put on the table that point to many.
External Key is a lexical attribute (or set of lexical attributes) that values are always identify an object instance.
ERD (Entity Relationship Diagram)
ERD is a model of a network that uses word order is stored in the abstract system.
Differences between the DFD and ERD
DFD is a model of network functions that will be implemented by the system
ERD is a model that emphasizes the network data on the structure and relationship data
Elements of the ERD
Entity
In the ER Diagram Entity is described with the form of a rectangle. Entity is something that exists in the real system and the abstract where the data stored or where there are data.
Relationship
ER diagram on the relationship can be described with a lozenge. Relationship is a natural relationship that occurs between entities. In general, the name given to the verb base making it easier to do the reading relation.
Relationship Degree
is the number of entities participating in a relationship. Degree which is often used in the ERD.
Attribute
is the nature or characteristics of each entity and relationship
Cardinalities
Tuple indicates the maximum number that can be relation with entities on the other entity
Degree of relationship
Unary Relationship
model is the relationship between the entity originating from the same entity set.
Binary Relationship
model is the relationship between 2 entities.
Ternary Relationship
is a relationship between the instance of 3 types of entities are unilateral.
KARDINALITAS
There are 3 cardinalities relations, namely
- 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.
- 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 show. for an incident on the first entity can have any relationship with more incident on the second entity, if the one incident on the the second entity can only have one relation with the incident on the first entity.
- Many To Many: if any incident occurs in an entity much have relationships with other entities in the incident.
EXEMPLARY KARDINALITAS

Notation (E-R diagram)
Symbolic notation in the ER diagram is
1. Rectangle represent the collective entity
2. Circle represent the attributes
3. Rhombic express relationship gathering
4. Line as the set of relationships between the entity and the collective entity with its attribute

DFD QUIZ

2009-04-05T04:32:00.000-07:00

Data flow diagram :

• Depicting the division of system into smaller module
• Facilitating less comprehending user of computer area to understand system to be done.
diagram context :
• Consist of one process and depict scope from a system
• Representing highest level of DFD depicting entire/all input to and system of output of system
• System limited by boundary ( depicted by dash line)
• There may not be any is depository ( storage)
Diagram zero :
• Depicting process of DFD
• Opening on to by totally system handled, showing existing especial process or function, data stream and of external entity
• At this level is enabled by the existence of data of storage
• For process which is not detailed again at level hereinafter hence enhanced by symbol ‘*’ or ‘ P’ by the end of process number
• Input balance and of output ( balancing) between diagram 0 with context diagram have to be looked after
diagram detailed :
• Diagram elaborating process what there is in diagram zero or level above him
• level number at DFD :
Name of Level Name of Diagram Process number
0 Context
1 Diagram 0 1.0, 2.0, 3.0, ...
2 Diagram 1.0 1.1, 1.2, 1.3, ...
3 Diagram 1.1 1.1.1, 1.1.2, ...
• In one level shall not there are more than 7 process and maximal 9, if more hence must be done decomposes
SPECIFICATION OF PROCESS
• Every process at DFD have to have the specification of process
• At method level top used to depict process earn by using descriptive sentence
• At more level detailed that is at process most under ( primitive functional) requiring the specification of more structure
• Specification of process will become guidance to programmer in making program ( coding)
• Method which is used in specification of process: breakdown of process in the form of story, table decision, tree decision
EXTERNAL UNITY.
• Something that beyond system, but he give data into system or give data of system
• Symbol with notation box
• External [of] entity [do] not the including the part of system
• Naming:
 Name of terminal in the form of noun
 Terminal may not have the name of same except its same object is true
CURRENT DATA
• Representing place emit a stream of information
• Depicted with connective straight line of component of system
• Data current shown with direction bow and line called of data current emitting a stream of
• 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
• Guidance giving of name
 Name of data stream which consist of some word stream attributed to continued line
 There may not be any data stream which it’s same name and giving of name have to express its contents
 Data stream which consist of some element can be expressed with element group
 Avoid usage of word ‘ data’ and ‘ information’ to give the name of data stream
 As possible the name of data stream written is complete
• Other rule :
 Name of data stream which come into a process may not is equal to name of secretory data stream of process
 data of Flow which step into or go out from data of storage needn't be called by if :
 comprehended easy and simple Data stream
 Data stream depict entire/all data item
 There may not be any data stream of terminal to data of storage or on the contrary because terminal non part of system, terminal with data of storage have to process
Process :
• Process represent what done by system
• Process can process data stream or data enter to become exit data stream
• Functioning process is to transforming one or some input data become one or some output data as according to specification of which wanted
• Every process have one or some input and also yield one or some output
• Process also referred as by bubble
• Guidance of giving of process name :
 Name of process consist of noun and vb. expressing process function
 Don't use word process as part of the name of a bubble
 There may not be any some process owning the name of is same
 Process have to give by number. Number sequence as possible follow process sequence or stream, but that way meaningless number sequence absolutely represent sequence process chronologically
Data storage
• Data Storage represent existing data repository in system
• Symbol with a couple of parallel line or two line wrongly one side from other side openly
• Process can take data from or give data to database
• Guidance of giving of name :
 Name have to express data of storage
 If its name more than one word hence have to say the word to joint
DICTIONARY DATA
• Functioning assist perpetrator of system to interpret application in detail and organizational all used by data element is system precisely so that user and system analyst have is same congeniality base about input, output, depository and process
• At analysis phase, data dictionary used as by communication means between system analyst with user
• At phase scheme of system, data dictionary used to design input, database and report
• Data current at DAD have the character of globally, boldness more detailed can be seen at data dictionary
• Data dictionary load the followings :
 Name of data current: have to be noted reader to needing furthermore clarification about a data current can look for it easily
 Alias: name or alias of differ from data can be written by if there are any
 Data form: used to group data dictionary into its use time scheme of system
 Data current: showing where from data emit a stream of and where data go to
 Clarification: giving clarification about meaning of data current
BALANCING IN DFD
• Stream Data which come into and go out from one process have to equal to data stream which come into and go out from detail of process at level / level below
• Name of data stream which come into and go out from one process have to equal to name of data stream which enter into and go out from detail of process
• Amount and name of entities external from a[n process have to equal to name and amount of entities external from detail of process
• Things which must be gave attention to DFD owning more than one level :
 Have to there are input balance and of output between one and level of level next
 Balance between level 0 and level 1 seen at input / output of data stream to or from terminal at level 0, while balance between level 1 and level 2 seen at input / output of data stream to / from pertinent process
 Name of data stream, data of storage terminal and at every level have to be same if its same object
PROHIBITION ORDER IN DFD
• Current Data may not from direct external entities go to other external entities without passing a process
• Data current may not from direct data deposit go to external entities without passing a process
• Data current may not from direct data deposit go to other data deposit without passing a[n process
• Data current from one direct process go to other process without passing a[n data deposit better / can possible avoided

third quiz

2009-03-07T22:16:00.000-08:00

Development of information system
Why require to develop system information?
system development can mean to compile a system of a new system to replace the system old ones as a whole or improve repair the system which there have. system old ones require to be improve repaired or changed because several things, that is as follows:
 Existence of Problems ( problems)
 do not all right in Organizational Growth System
 To Reach for the opportunity ( opportunities)
 Existence of instruction ( directives)
system development Target
• Solving problems
• Reach for the opportunity
• Fulfilling given instruction
What expected at new system?
• Performance ( performance)
- Measured to use the throughput and response time
• Information ( information)
- Make-Up of information quality
• Economy ( economic)
- Make-Up of benefit of vs. decreasing cost
• Control ( operation)
- Detecting and improve repairing mistake
• Efficiency ( efficiency)
- Efficient of operational
• Services ( service)
- Make-Up of system service
system development Principle.
• System for the management of
• System is big investment
- Investigation of all alternative ( minimizing missing opportunity cost)
- Best investigation have to be valuable : cost-benefit analysis & cost-effectiveness analysis
• System need the educated people
- Do not education have to be formal
• Step work the System Development life cycle
• System development do not have to massage
• Don't fear to cancel the project
• System documentation
System development life cycle
Model Waterfall
Phase model the Waterfall
• Analyze and requirement definition
• Design of System and software
• implementation And unit testing
• integration And testing system
• Operate for and maintenance Insuffiency from model waterfall difficulty to accommodate the change after process walk.

Problems Model the Waterfall
• Inflexible in project division to in different storey level
• Difficult to responded of requirement change consumer
• So that model this compatible only if requirement have been understood better.

Model Iteratif

Model Spiral

Sector Model The Spiral
 Objective Setting
- special Objective for the phase of identified the
 estimating And risk reduction
- Risk appraised an activity used to lessening risk.
 development And Validation
- Model the development for the system of selected which is in the form of model generic
 Planning
- Project of next review phase and from spiral planned.

system development Approach.
• Classic approach of vs. of structure approach
• approach of Rasher of vs. of system approach
• approach of bottom - up vs. of approach top - down
• approach of totally system vs. of approach modular
• Approach of jumping movement far vs. approach expand
system development Approach.
 Classic approach of vs. of structure approach
- Classic approach
• Step in SDLC
• Do not involve the consumer, more emphasizing of system analyst
• Problems: difficult development, costly treatment expense, big mistake possibility, efficacy less be well guaranteed, internal issue applying
- Structure approach
• Consumer involved from early to determine the system requirement
• Using tools-tools of like data of flow diagram

 approach of Rasher of vs. of system approach
- Rasher approach
• Emphasizing at a[n application or activity
• Heedless of the target of overall of System approach
• See system as one intact union
• Emphasizing at goal achievement as a whole

 approach of bottom- up vs. of approach top - down
- approach bottom-up
• Started from level of under that is operational
• Representing approach marking classical
• Recognized with the term data-analysis
- approach top-down
• Started from level for that is strategy planning
• Representing marking of structure approach
• Recognized also by decision-analysis

 approach of totally system vs.. of approach modular
- approach totally system
• Developing system at a time and totally
• Representing classic approach marking
- approach Modular
• Breaking complicated system become the parts of simple
• System developed become on schedule, easy to be comprehended and looked after

 Representing marking of structure approach
- approach of long jump vs. approach expand the
• approach long jump ( great-loop approach)
• Developing system at a time use the sophisticated technology
• High risk and finish a lot of expense
- Approach expand the ( evolutionary approach)
• Applying sophisticated technology for the application of certain
• Developed to follow the requirement
• Cost effective and can keep abreast of technology
system development Methodologies.
What that methodologies?
- Method used in science
What is method?
- A way of systematic to do something
What that algorithm?
- Procedure medley to solve a[n problem
classification of development Methodologies.
 Functional Decomposition
- Emphasizing system resolving become the subsystem
- Follow the example of the: HIPO, Stepwise Refinement, iterative stepwise refinement, information hiding
 Data-Oriented
- Emphasizing at processed data characteristic
• Data-flow Oriented: module of according to data element type
• Data-structure Oriented: structure of input and output
 Prescriptive
- usually provided by factory of software maker
Appliance in system development.
 In form of graph: HIPO, SADT, Jackson’s Diagram, and others
 Appliance using schema:
- Activity Charting: depicting activity, follow the example of the: Gant Chart, flowchart, etc
- Layout Charting: depicting arrange situation.
- Personal Relationship charting: depicting personnel relation/link, follow the example of the: organization chart, working distribution chart
system development Technique.
 Technique of project Management ? for the schedule of project, follow the example of the: CPM And PERT
 Technique find the fact ? to collect and determine the data / fact
- Interview the
- Observation
 Technique analyze the expense benefit ? cost-benefit and cost-effectiveness analysis
 Technique run the meeting
 Inspection technique
System Analyst & programmer.
 System analyst: learning problem and determine the requirement of system wearer to identify the resolving
 Programmer : writing code program pursuant to designing to develop build which is made by an analyst
 System analyst undertake to link the knowledge difference that happened between wearer of system and programmer
needed knowledge.
data processing Technology, computer and programming.
 Business knowledge in general
 Quantitative method: regress, linear of programming ,etc
 Trouble-Shooting membership
 Communications Membership usher the personnel
 Membership construct the relation/link usher personnel

basic concept of Information System Analysis and Design

2009-02-20T19:22:00.000-08:00

Basic Concept of Information Systems Analysis and Design

Before studying what that Information Systems Analysis and Design, first we have to know what that system and what that information.

WHAT IS SYSTEM?

There are two approaching to definition of system:

1. Definition of system based on approach of procedure

According to this approach, system interpreted by as a working network from procedures which is interaction and work along to finish a specific-purpose or goal. A procedure is a correct sequences of instruction steps explaining what have to be done, who have to do, when have to be done and how to do that.

2. Definition of system based on approach of element

According to this approach the definition of system is a set of elements which is have interaction to reach specific-purpose or goal.

CHARACTERISTIC OF SYSTEM

Characteristic a system can be explained as follows:

1. Components

Consist of a number of components which interact, what each other working along to form an unity. The example is Supra System that is a larger ones system.

2. Boundary

A system has a boundary to limiting system with environmental or other system outside its.

3. Environments

Environment is a media link between a subsystem with other subsystem.

4. Input

Entered energy into system can in the form of treatment input and signal input. The treatment input is entered energy system to can walk. While signal input is energy which in process to yield output.

5. Output

The result from processed energy and classified is become an output which good for and rest of dismissal.

6. Process

Process is the change an input become output.

7. Target (objective)/goal

Otherwise have the target then system operation there will be no utilizing of. The system is told succeed if it has reach the target/its goal.

The Classification Of System
a. Deterministic System
The Certain system operate with behaviour which have earned can be predicted, interaction between its sharess can be detected categorically so that its output can be forecasted. for example of : Computer programe, executing precisely as according to its instruction network. System of pay, and others.
b. Probabilistic System
The System which is input and its process can be defined, but yielded output cannot be determined categorically; ( always there is a little mistake / deviation to forecast of the way system). for Example : marketing system)
c. Open System
The system that relation and effect external environment .This system accept input and yield output for external environment / the other sub system, so that have good operation system. This system tend to measure up to adaptation, can adapt to its environment so that can continue its.
d. Closed System
The System Physical where the process that happened do not experience of transfer of items, information or energy with environment outside system. This system work automatically without existence of interfere in of external side of it.
e. Relatively Closed System
The closed System but doesn't closed at all to accept other influences. This system in its operation can accept influence from outside which have been defined in certain boundarys.
f. Artificial System
The System imitating occurence in system. This system is formed pursuant to occurence in nature where human being unable to do it. Equally imitat exist in nature.
g. Natural System
The natural System is occurence in nature. for Example of : sea, solar system and others.
h. Manned System
The System explanations of behaviour covering human being taking part in. This system can be depicted in way of as follows:
The System of Human being focus the relations between human being
The System of Human being - Machine, System which involve machine to a target
The Machine System, automatic system where human being have duty to start and finish system, meanwhile human being entangled also to monitor system.

Information
Data is fact. Information is data that processed become better form and more meaning to accept it. If data is not useful to accept it so the data cannot be referred as by information.

QUALITY OF INFORMATION

To get information with quality, then information must have:

*
Accurately

Information free from mistakes and doesn't deflect or mislead
*
Punctually

Incoming information at receiver may not lose time
*
Relevantly

Information is have benefit for its usage.

Information will be valuable if big added significance of expense get it