Sunday, May 3, 2009

ERD quiz

ERD quiz
ERD

From ERD diagram above there is 2 error, that is:
• No cardinality between table BAGIAN and PROYEK.
• To determine foreign key between table PEGAWAI and BAGIAN on relation PIMPIN.
• No relation from table PROYEK to ternary, because table PROYEK has have relation KERJA with table PEGAWAI.
So, I try to improve ERD as following:
ERD


• I give cardinality between table BAGIAN to table PROYEK with relation 1 to N (one to many).
• I give participation from table BAGIAN to table PEGAWAI the relation is total, in order to I can determine which one table that get foreign key from relation PIMPIN.
• I remove relation between table PROYEK to ternary, because table PROYEK has have relation KERJA with table PEGAWAI.

MAPPING
NORMALISASI
1NF and 2NF



For table TANGGUNGAN and KERJA don’t need to normalization, because that tables don’t have primary key.
For the 3NF normalization. First, determine attribute from above which have transitive dependency, that is:

Sunday, April 26, 2009

Normalization

Normalization

Normalization process is the establishment of the database structure so that most of the ambiguity can be removed. Normalization stage, starting from the most mild (1NF) to most stringent (5NF). Usually only up to the level of 3NF or BCNF because already sufficient to generate the table-a table of good quality. Normalization is a systematic way of ensuring that a database structure is suitable for general-purpose querying and free of certain undesirable characteristics—insertion, update, and deletion anomalies that could lead to a loss of data integrity.

Normal form (normal form) is a database of the scheme class relations defined for the purpose of high integrity and maintainability. Creation of a normal form is called normalization. Normalization achieved with analysis dependence among the attributes of each individual associated with that relation.

Normalization database
Normalization be used to optimizing table structures, increase speed, the income data is the same, more efficient in the use of storage media, reduce redundancy, avoid anomalies (insertion anomalies, deletion anomalies, update anomalies), improved data integrity.

A table saying good (efficient) or if the normal 3 to meet the following criteria:

  • If there is decomposition (decomposition) table, it must be guaranteed safe the composition (Lossless-Join Decomposition). That is, after the table is described a new table-table, the table-table can generate a new table with the same exact.
  • Maintain dependence on the functional changes in data (Dependency preservation).
  • Does not violate Boyce-Code Normal Form (BCNF).

If the three criteria (BCNF) can’t be met, then at least the table does not violate the Normal Form of the third stage (3rd Normal Form / 3NF).

Functional Dependency

Functional Dependency attributes describe the relationship in a relationship.
An attribute said functionally dependant on the other, if we use the value attribute to determine the value of the other attributes.
Symbol that is used to represent à functional dependency. Read the functional set.
Notation: A à B
A and B are attributes of a table. A means of determining the functional B or B depends on A, if and only if there are 2 rows of data with the same value of A, then B is also the same value
Notation: A xà B
It is the opposite of the previous notation.






Functional Dependency of the table value

Functional Dependency:

NRP à Nama

Mata_Kuliah, NRP à Nilai

Non Functional Dependency:

Mata_Kuliah à NRP

NRP à Nilai

Nrp à Name
Because for each value Nrp the same, then the value of the same name
(Mata_kuliah, NRP) à Value
Because the value of attributes depending on the NRP and Mata_kuliah together. In another sense Mata_kuliah for the NRP and the same, they also rated the same, because Mata_kuliah and the NRP is a key (is unique).

NRP ≠> Mata_kuliah
Value ≠> NRP

First Normal Form - 1NF

Relations, there is a condition in First Normal Form (1NF) if and only if all domains are covered only atomic value, for example, there is no recurrence group (domains) in a tuple. Advantage of the 1NF relation compared Unnormalized (UNRs) is a simplification in the form of representation and ease of use in developing a query language. lack is the need to duplicate data, Most of the system relations (not all) require a form of relations in 1NF.

A table on the form said to be normal if I did not reside in the unnormalized form of a table, where there is a kind of field multiplication and field that allows a null (empty).
May not be found:

  • Many attributes of value (Multi valued attributes).
  • Attributes composite or a combination of both.
  • Price is the domain attribute must be atomic rates.

Second Normal Form - 2NF

A super key is a set of one or more attribute, which, taken in particular where the possible for us to uniquely identify one entity or relationship.

A Candidate key is a subset of attributes-the attributes that super key is also super key and not reducible to the other super key. A primary key is selected from the set of candidate key for use in relation to an index of the ownership of one or more of the attribute that can be defined from the unique value of one or more of the attribute called functional dependency.

Given a relation (R), a set of (B) is functionally dependent on another set of attributes (A) if, at one time, each value A associated with a value B, this is a form of the FD A → symbol with B. A relation is in second position to its normal form (2NF) if and only if the relationship is also in 1NF and every attribute non key fully dependent on its primary key. 2NF requires that any FD in the relation must include all components of the primary key as the determinant, either direct or transitive.

Why should 2NF, consider the benefits of the 1NF R. paper, pub-id, and editor-created duplicate id. For each author of the paper. If the editor of publications for a paper change, some also in the tuple must be updated. Finally, if one paper on the take, all the symbol tupple should be removed. This form will give the side effects on the deletion of information that a associated with the auth-id name and auth-auth-addr.

  • One way to do this is to transform the relations into two or more of the 2NF relations.

example R1: paper-id, id-auth-name → Inst, Inst-addrR2: auth-id → auth-name, auth-addrR3: paper-pub-id → id, editor-id.

Normal form 2NF met in a table if it meets the form of 1NF, and all the attributes than the primary key, have a full Functional Dependency on primary key.
A table does not meet 2NF, if there are attributes that dependency (Functional Dependency) are only partial (only depending on the part of the primary key).

If there are attributes that have no dependence on the primary key, then the attributes must be moved or removed.
Y is full if it is said to delete an Functional dependency X attribute A from X means that Y is no longer dependent functional.

Y said if deleting a partial attribute A from X means that Y is functionally dependent. Functional dependency .
R depend on the full functional primary key R.ÎRelation scheme R in the form 2NF if every non-primary key attribute A .

Third Normal Form - 3NF

Normal form 3NF fulfilled if the form meets 2NF, and if there are no non-primary key attribute that has a dependence on non-primary key attributes ofthe other (transitive dependenc

ies).

A relationship in the Third Normal Form (3NF) if and only if the relation is in 2NF and every non key attribute is non transitive dependent on primary key

Boyce-Codd Normal Form (BNCF)

Boyce-Codd Normal Form constraint has a stronger form of the Normal third. To be BNCF, relations must be in the form of first normal and forced each of the attributes depends on the function in the super key attributes.
In the example below there is a relationship seminar, is the Primary Key NPM + Seminar.

Students may take one or two seminars. Each seminar requires 2 each of the students and led by one of the 2 seminar. Each leader can only take one s

eminar course. NPM in this example and show a seminar guide.

Normal form of the fourth and fifth

Relations in the fourth normal form (NF 4) if the relation in BCNF and dependency tdak contain many values. To remove the dependency of many values from a relation, we divide the relationship into two new relations. Each relation contains two attributes that have a lot of relationship value.

Relations in fifth normal form (5NF) deal with the property called the join without any loss of information (lossless join). Fifth normal form (also called the 5 NF PJNF (projection join normal f

orm). The case is very rare and appear difficult to detect in practice.

Rules of Data Normalization

  1. Eliminate Repeating Groups

In the original member list, each member name is followed by any databases that the member has experience with. Some might know many, and others might not know any. To answer the question, "Who knows DB2?" we need to perform an awkward scan of the list looking for references to DB2. This is inefficient and an extremely untidy way to store information.

Moving the known databases into a seperate table helps a lot. Separating the repeating groups of databases from the member information results in first normal form. The MemberID in the database table matches the primary key in the member table, providing a foreign ke

y for relating the two tables with a join operation. Now we can answer the question by looking in the database table for "DB2" and getting the list of members.












  1. Eliminate Redundant Data

In the Database Table, the primary key is made up of the MemberID and the DatabaseID. This makes sense for other attributes like "Where Learned" and "Skill Level" attributes, since they will be different for every member/database combination. But the database name depends o

nly on the DatabaseID. The same database name will appear redundantly every time its associated ID appears in the Database Table.

Suppose you want to reclassify a database - give it a different DatabaseID. The change has to be made for every member that lists that database! If you miss some, you'll have several members with the same database under different IDs. This is an update anomaly.

Or suppose the last member listing a particular database leaves

the group. His records will be removed from the system, and the database will not be stored anywhere! This is a delete anomaly. To avoid these problems, we need second normal form.

To achieve this, separate the attributes depending on both parts of the key from those depending only on the DatabaseID. This results in two tables: "Database" which gives the name for each DatabaseID, and "MemberDatabase" which lists the databases for each member.

Now we can reclassify a database in a single operation: look up the DatabaseID in the "Database" table and change its name. The result will instantly be available throughou

t the application.









  1. Eliminate Columns Not Dependent On Key

The Member table satisfies first normal form - it contains no repeating groups. It satisfies second normal form - since it doesn't have a multivalued key. But the key is MemberID, and the company name and location describe only a company, not a member. To achieve third normal form, they must be moved into a separate table. Since they describe a company, CompanyCode becomes the key of the new "Company" table.

The motivation for this is the same for second normal form: we want to avoid update and delete anomalies. For example, suppose no members from the IBM

were currently stored in the database. With the previous design, there would be no record of its existence, even though 20 past members were from IBM!







  1. BCNF. Boyce-Codd Normal Form

Boyce-Codd Normal Form states mathematically that:

A relation R is said to be in BCNF if whenever X -> A holds in R, and A is not in X, then X is a candidate key for R.

BCNF covers very specific situations where 3NF misses inter-dependencies between non-key (but candidate key) attributes. Typically, any relation that is in 3NF is also in BCNF. However, a 3NF relation won't be in BCNF if (a) there are multiple candidate keys, (b) the keys are composed of multiple attributes, and (c) there are common attributes between the keys.

Basically, a humorous way to remember BCNF is that all functional dependencies are:
"The key, the whole key, and nothing but the key, so help me Codd."

  1. Isolate Independent Multiple Relationships

This applies primarily to key-only associative tables, and appears as a ternary relationship, but has incorrectly merged 2 distinct, independent relationships.

The way this situation starts is by a business request list the one shown below. This could be any 2 M:M relationships from a single entity. For instance, a member could k

now many software tools, and a software tool may be used by many members. Also, a member could have recommended many books, and a book could be recommended by many members.










So, to resolve the two M:M relationships, we know that we should resolve them separately, and that would give us 4th normal form. But, if we were to combine them into a single table, it might look right (it is in 3rd normal form) at first. This is shown below, and violates 4th normal form.








To get a picture of what is wrong, look at some sample data, shown below. The first few records look right, where Bill knows ERWin and recommends the ERWin Bible for everyone to read. But something is wrong with Mary and Steve. Mary didn't recommend a book, and Steve Doesn't know any software tools. Our solution has forced us to do strange things like create dummy records in both Book and Software to allow the record in the association, since it is key only table.

The correct solution, to cause the model to be in 4th normal form, is to ensure that all M:M relationships are resolved independently if they are indeed independent, as shown below.


  1. Isolate Semantically Related Multiple Relationships

modify the original business diagram and add a link between the books and the software tools, indicating which books deal with which software tools, as shown below.


This makes sense after the discussion on Rule 4, and again we may be tempted to resolve the multiple M:M relationships into a single association, which would now violate 5th normal form. The ternary association looks identical to the one shown in the 4th normal form example, and is also going to have trouble displaying the information correctly. This time we would have even more trouble because we can't show the relationships between books and software unless we have a member to link to, or we have to add our favorite dummy member record to allow the record in the association table.


The solution, as before, is to ensure that all M:M relationships that are independent are resolved independently, resulting in the model shown below. Now information about members and books, members and software, and books and software are all stored independently, even though they are all very much semantically related. It is very tempting in many situations to combine the multiple M:M relationships because they are so similar. Within complex business discussions, the lines can become blurred and the correct solution not so obvious.


  1. Optimal Normal Form

At this point, we have done all we can with Entity-Relationship Diagrams (ERD). Most people will stop here because this is usually pretty good. However, another modeling style called Object Role Modeling (ORM) can display relationships that cannot be expressed in ERD. Therefore there are more normal forms beyond 5th. With Optimal Normal Form (OMF), it is defined as a model limited to only simple (elemental) facts, as expressed in ORM.

  1. Domain-Key Normal Form

This level of normalization is simply a model taken to the point where there are no opportunities for modification anomalies.

"if every constraint on the relation is a logical consequence of the definition of keys and domains"

Constraint "a rule governing static values of attributes"

Key "unique identifier of a tuple"

Domain "description of an attribute’s allowed values"

Trivial functional dependency

A trivial functional dependency is a functional dependency of an attribute on a superset of itself. {Employee ID, Employee Address} → {Employee Address} is trivial, as is {Employee Address} → {Employee Address}.

Full functional dependency

An attribute is fully functionally dependent on a set of attributes X if it is

· functionally dependent on X, and

· not functionally dependent on any proper subset of X. {Employee Address} has a functional dependency on {Employee ID, Skill}, but not a full functional dependency, because it is also dependent on {Employee ID}.

Transitive dependency

A transitive dependency is an indirect functional dependency, one in which XZ only by virtue of XY and YZ.

Multi valued dependency

A multi valued dependency is a constraint according to which the presence of certain rows in a table implies the presence of certain other rows.

Join dependency

A table T is subject to a join dependency if T can always be recreated by joining multiple tables each having a subset of the attributes of T.

Super key

A super key is an attribute or set of attributes that uniquely identifies rows within a table; in other words, two distinct rows are always guaranteed to have distinct super keys. {Employee ID, Employee Address, Skill} would be a super key for the "Employees' Skills" table; {Employee ID, Skill} would also be a super key.

Candidate key

A candidate key is a minimal super key, that is, a super key for which we can say that no proper subset of it is also a super key. {Employee Id, Skill} would be a candidate key for the "Employees' Skills" table.

Non-prime attribute

A non-prime attribute is an attribute that does not occur in any candidate key. Employee Address would be a non-prime attribute in the "Employees' Skills" table.

Primary key

Most DBMSs require a table to be defined as having a single unique key, rather than a number of possible unique keys. A primary key is a key which the database designer has designated for this purpose.

Friday, April 3, 2009

DATA FLOW DIAGRAM

DATA FLOW DIAGRAM
Data Flow Diagram (DFD) is a means of making the model system allows the professional to describe the system process as a functional network that is connected to one with flow data, either manually or computerized. DFD is a tool of making a model that provides emphasis only on the function of the system. DFD is a tool that system design-oriented flow data with the concept of decomposition can be used to depiction and analysis of system design that is easily
communicated by professionals and users to the system the program.
Also called Data Flow Diagram (DFD) to describe the system modules in a smaller, easier and less understanding of the field to understand the computer system that will be done.

Diagram context
• include one process and expressed scope from a system
• it's the highest level from DFD which expressed all input into the system and output from system
• System is bounded by the boundary (it's shown by the dashed line)
• there isn't any storage

This diagram is the highest-level diagram of the DFD describes the relationship with the environment outside the system.
1. Specify the name of the system.
2. Determine the limits of the system.
3. Determine the terminator are present in the system.
4. Determine what is received / given terminator from / to the system.
5. Drawing context diagram.

Zero diagram
1. Describes process of DFD.
2. Providing views on the overall system in which, showing the main function or process that is, the flow of data and entity external
3. At this level of data storage possible
4. To process that does not detailed again on the next level then added to the symbol '*' or 'P' at the end of the process
5. Balance of input and output (balancing) between 0 to diagram context diagram should be maintained

Detailed Diagram
Detailed Diagram is diagrams that decompose a process that is in the diagram zero level or above
Numbering level in the DFD.
In one level there should be no more than 7 units and the maximum of 9, when more should be done in the decomposition

SPECIFICATION PROCESS
Each process in the DFD must have a specification process
At the top level method is used to describe the process can use a sentence with descriptive
At a more detailed level, namely on the bottom (functional primitive) requires specification of a more structured
Specification process will be the guideline for the programmer to make this program (coding)
Method used in the specification process: the process of disintegration in the form of a story, decision table, decision tree.

ON FOREIGN
1. Something that is outside the system, but it provides data in the system or to provide data from the system
2. Symbol with the notation
3. External entity not part of the system including
4. Naming:
• The name of the form of noun
• Terminal may not have the same name except the same object
Sure every system has a limit system (Boundary) that a separate system with the outside environment. System will receive input and produce output to the outside environment. Unity outside (external entity) is the unit (entity) in environment outside the system that can be a person, organization or other system that is located outside in environment that will provide input or receive output from the system.

DATA FLOW
• Is the place flow information
• Depicted with the straight line that connects the components of the system
• Data flow direction is indicated with arrows and lines give the name on the flow of data that flows
• Flow data flow between processes, data storage and data flow indicates that the form of data input for the system
Data flow in DFD is given an arrow symbol. This data flow between processes, store data, and external entity. This data flow represents the flow of data can be input to the system or the results of the processing system.
1. Packet of data
When two or more of a source to the same destination the same, it should be considered as a single stream of data, because two or more data flows together as a package. The data flow must be indicated as with the data flow, even though for example consist of several documents.
2. Diverging data flow
Data flow that spreads shows a number of copies of the same data flow from the same source to different purposes.
3. Converging data flow
Gather flow data showed that some of the data flow that is different from different sources to join with the same goal.
4. Cracked the concept and purpose of data flow
All data flow must be generated from a process (can be one or both, that is derived from a process or not come from a process but a process leading to or coming from a process and to a process). Concept is important because the flow of data is one of the results of a process or will be used to perform a process.

Processes
• The process is what is done by the system
• The process can process data flows or data entry into the flow of data out
• Transform the process of working one or more of the input data into one or more of the output data in accordance with the desired specifications
• Each process has one or more inputs and produce one or more output
• The process 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

A process is an activity or work done by the people, machines, or the results of a computer data that flow into the process to produce data that will flow out of the process. for physical data flow diagrams (PDFD), the process can be done by people, machinery, computers and for logical data flow diagram (LDFD), a process only shows the process from the computer.
a. Identification data
This identification included of a number that shows the reference number of the process.
b. Process name
the name of the process shows what is done by the process.
c. Processing
PDFD to indicate that the process is not only the process of the computer but also a manual process, such as the process is done by people, machinery, and so forth. This shows the processor who or where the process is done. LDFD, here for as a processor is program that the process referred.

DFD error location is:
• Process does not have any input but the output, this error is called black holes, because the data into the process and the like disappeared into a black hole.
• The input process but did not receive the input, the error is called the miracle.

Data storage
a. Data storage is a storage place for data that exists in the system
b. Symbol with a pair of parallel lines or two lines with one side open side
c. The process can retrieve data from or provide data to the database
d. Guidelines of the name:
• The name should reflect the data storage
• When his name more than one word must be marked with the number


Data dictionary
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 process. At analysis, the data dictionary is used as a means of communication between the systems analyst with the user. At the system design, data dictionary is used to design input, reports and databases. Flow data on the global DAD, further details can be seen in the data dictionary.


Contain of Data dictionary
1. Name of data flow: must note that readers who need further explanation about a flow of data can find it easily.
2. Alias: alias or other name of the data can be written when there is.
3. Forms of data: used to segment the data dictionary to use when designing the system.
4. Flow data: indicates from which data flows and where the data.
5. Description: to give an explanation of the meaning of the data flow.
6. Period: at the occurrence of the data showed, that the DD can know when the input is input to the system, when the program is done, and when the report produced.
7. Volume: the volume should be noted is the volume average (the average number of flow data that flows in a certain period) and the peak volume (highest volume). Volume is how much to use external storage to be used.
8. Structure data: shows the flow of data recorded in the DD of the items whatever.

Balancing IN DFD
a. The flow of data into and out of a process must be the same as the flow of data into and out of the details of the process on the level / levels below.
b. Name of the data flow into and out of the process must match the name of the flow of data into and out of the details of the process.
c. Number and the name of an entity outside the process must be equal to the number of names and entities outside of the details of the process.
d. The issues that must be considered in the DFD which have more than one level:
• There must be a balance between input and output of one level and next level.
• Balance between level 0 and level 1 at the input / output of stream data to or from the terminal on level 0, while the balance between level 1 and level 2 is seen on the input / output of stream data to / from the process concerned.
• Name of the flow of data, data storage and terminals at each level must be the same if the same object.

Restrictions in DFD
a) Flow data may not be from outside the entity directly to other outside entities without going through a process.
b) Flow data may not be from the savings directly to the data to outside entities without going through a process.
c) Flow data may not be saving the data directly from the savings and other data without going through a process.
d) Flow data from one process directly to the other without going through the process of saving data should / be avoided as much as possible

Saturday, March 28, 2009

INITIAL INVESTIGATION and REQUIREMENT ANALYSIS

INITIAL INVESTIGATION and REQUIREMENT ANALYSIS
System Investigation Concepts
Problem is difference (gap) between system purposes and condition of the system be in fact, with other understanding why do system fail to reach the system purpose which have been determined before all.
To know the things any kind of do which have caused failure of system, hence a analyst better do the investigation in advance before conducting action to improve the system. With investigation, a analyst will be more comprehend his system path and problem more circumstantial, though in detect problem have been known the problems but still depict its outline.
Many reports in detecting the problem might not really indissoluble or real. Possible mentioned because of:
a. The purpose too difficult ideal so that or might not will reach.
b. System cannot be developed for want of resource, attitude or both.
c. Measurement of inaccurate system.
d. Statement of system purpose which have under developed (statement of goals is dated).
e. Difference between ideal systems and system is in this time in character whereas (the gap between the ideal and the current system is temporary and will decrease given patience).
In phase problem solving, better give the explanation concerning:
a. Formulation of the system condition walking passing activity of investigation in detail.
b. Get the ideal system consensus.
c. Develop some alternatives to lessen difference (gap) between ideal systems with is system walk.
d. Choose the best alternative and sell it to management.
Duty start point b shall d will eat the sufficient time including the expense required. Intention of investigation is to setle or show the problem be in fact happened beside as mode a analyst to understand his system exhaustively.

Constraint in system of investigation
In doing the investigation there are some resistances or constraint to happened, that is problem of:
a. Time
Analyst lack time resource, so that only doing some of activities of investigation. Usually time relate to the required expense problem.
b. Cost
Oftentimes released expense relate to the duration time for activity investigation, so that management will give the constrain expense of.
c. Knowledge
Manager information system give order to the junior analyst which not yet owned technical membership or the knowledge enough, so that will affect the investigation result less sharpen, bake or complete.
d. Politics
Certain management sides or possibly propagate the issues of the purpose to pursue activity of investigation.
e. Interference
Is there are of the sides trying the interference or arrange in activity investigation so that will hellion or raise a bobber.
Recommendation
Result of investigation is a recommendation, what one of them is as follows :
a. Don't bring an action against any because is not found the problem.
The mentioned can happened because possibly in preliminary report, problem of him pretended so that at the time of done the problems investigation don't happened or don't be found.
b. Do conservancy of system to problems the smallness.
Conservancy of done system every day (short period) will assist the minimization problems which emerge so that quickly to be handled and always controlled well.
c. Improve ability or skilled of user in running or use the information system.
d. Allow for the system modification totalize, so that idea require to change it with new system.
e. Place the problem that happened at the system development plan is soon done.

Tactics of investigation
a. Listen, do note lecture.
If you know all answers, sure you will not do the investigation.
In activity of investigation better give enough time for management side or user to explicate and clearly and system analyst doesn't predominating of discussion.
b. Don't give the resolving early to problem (do not presolve the problem).
Mean don't try to show the idea to solve problem, before all activity of investigation is completed done, so that avoid the solutions blow by blow.
c. Compare stories.
People mean to differ the view to same problem, so that require to entangle supervisor and subordinate in opening on to the problem clearly and reliably. Shall not listen from 1 source so that there's only one view (opinion). When user have difference of view, better look for his difference and then look for the view have equality.
d. Look for reluctant responses.
Disinclination give something that indication comments hidden. Too much system problems can also cause confusion so that unable to explicate.
e. Probe for logical inconsistencies.
Logical inconsistencies is stop flow data where the data lose, or suddenly emerge the selected data. Some matters related to this problem:
- There is data enter him but there no output (black hole).
- There is output but there no input data (miracles).
f. Observe your effect.
Observe difference of user when you attend and moment you is absent. Assessment is is directly referred with internal probe. Is while external probe is done assessment undetected by whoever (searching external of material), be like by report analysis, history problem former, and source of investigation secondary other.
g. Expect hard, bowling work.
Become the patient and professional detective in handling problems of system bertahap.dan continually.
h. Avoid politics.
Analyst system mission fact is not judging (your mission is fact, not judgement).

Technique of investigation
Technique of investigation covering activity:
a. Directly ( direct ( internal) probes)
That is to know directly what is going on in user environment. They permit you to observe direct it without through selected sides (interpreter). Internal probes is the source of chaos (disruptive), because arising difference of attitude. Internal probes used as rich (a richer) and group justifier from fact that happened (truer group of facts). There are three technique to do the direct investigation, that is with:
- Questionnaires.
This technique precise very, if in investigation have the expense and time constraint. Though get it from respond through form stuffing. As for things in questionnaire condition of explanation will differ if look in the face directly (face to face interview).
Best matter from questionnaire is as document able to show differences that happened at responder.
- Interview.
This activity required the specialty and time. Everybody can not do the question and answer successfully. Interview question can applicable to successive exhaustively beside more flexible as according to field condition. Constraint the faced is time and specialty.
- Observation.
Is internal probe the strength (a powerful internal probe).
Sit down with user of system by doing the perception with the question more specific. Why you do this activity?
or where this document will be removed ?. Every question possibly can show the mysterious trouble-shooting.
b. Indirect (external) probes
Activity able to be done swiftly and invisible of operational personal, so with this can know the external side or something that hidden from user community. This activity will predominate in the early of activity SDLC, internal hereinafter probe to deepen.
- Procedure flow.
Procedure operational is medium (vehicles) for officer is newly understand his work and experience of employees to handle the problem.
If procedure flow not true, information system cannot be operated correct also. Use system flowchart to trace the way information as explanation procedure his operation.
If is problems of procedure, the problem possibly will arise in the operational be in fact.
- Document review.
Is by getting and collect the important document (critical document). If problem happened many in customer orders, collect the original document source from customer orders which used as by the entry data, interactive screen format, detail transaction, summary and mistake of report that happened. Document is oftentimes become the cause of problem.
- Sampling.
You require information from vendor billing which have given the discount at the time of payment, because company of discount moment money loss is not given on the happening of delay of payment.
You can entangle customers of payer to get the information (despite of many transactions). Finally you can list sample data with election random for the one of last week, choose 20 page of daily transaction, choose 5 item from each chosen page, record the information to each 5 item and count average and variant to samples from all payment transactions that happened.
- Tabular tools
Referred also matrix, that is checklists to find discrepancies in transaction path

Description system is in this time
Determine the system performance in this time will find difficulties if company don't have a standard measurement of system performance.
What a pity, company tend to don't renew (to update) the system documentation walking. Hence, analyst improve the document during investigation problem of system.
Description system is in this time cover the explanation:
a. Inputs
b. Outputs
c. Files
d. Data elements
e. Transaction and action document volume
f. Data flow diagrams

Requirement analysis.
intensive Interaction phase between system analysts with end user where system development team show his membership to get the comments and trust of user so that get the good participation.
4 Purpose which want Reachable:
- Explain the complete system.
- Depict the ideal information system.
- Bring the ideal information system to condition in this time by paying attention the resource constraint.
- Give the motivation to confidence of user into system development.

Phase requirement analysis is intensive interaction phase between system analysts with community user of system (end-user), where team system development show his membership to get the comments and trust of user, so that get the good participation. Is work difficult to get agreement (skeptical) user concerning their requirement from a information system, because possibly natural user failure of information system before all.

Desire of user
Early stage in requirement system is do survey to desire of user and explain the ideal information system.
Ideal here is conceptual than reality, mean that there is no perfect information system but having the character of subject. If this matter is not explained exhaustively can generate difference of view or will disappoint end-user.

Method requirement of analysis
Election of data collecting method require to correct during doing requirement system. The method is interviews, questionnaires, observation, procedure analysis, and document survey.
Method:
- Interview.
1. How that method is used.
• Election potential interviewees.
• Make agreement to potential interviewees.
• Prepare the complete question structure and clearly.
• Choose person which be interviewed personally and record it.
2. Goals of method.
• Personal key in course of DFD.
• sometimes entangle the outsider, be like customer or vendors.
3. Advantage of method.
• Interviewer can measure respond through question and accommodate it according to situation that happened.
• Good to the problems don't structure, be like why you think this matter can happened?
• Show impression interviewer personally.
• Peeped out the high response since compilation of meeting.
4. Loss of method.
• Require the expense and time by dozens.
• Require the special experience and training of interviewer.
• Difficult compare the report interview because subjective natural.
5. When is the method good used
• Get the explanation or view from personal key.
• Test credibility from interviewees.
• Look for interview which contradictions.
• Stabilize the credibility team.
Some important factors in interview the good, that is objectives, audience, format, weighting and combining responses, and documentation.
- Questionnaires.
1. How that method is used.
- Design by using standard questionnaire.
- Questionnaire delivered to environment work end-users.
- Structure respond summarized in distribution statistic.
2. Goals of method.
- All end-user with their horizon will be involved in the solution process resolving of system.
- End-User attributed to the process usage of symbols in DFD.
3. Advantage of method.
- Cheap and quickly from [at] interviews.
- Don't require investigator which train, only one required expert to design questionnaire to end-user chosen.
- Easy to predict the result of since making questionnaire.
- Easily minimization the expense of for all end-user.
4. Loss of method.
- Cannot make specific question for end-user.
- Cannot show the person end-user.
- Low comments for no of strong motivation to return questionnaire. Inadaptable of question to end-user specific.
5. When is the method of good to used.
- Simple It asking, and don't have the twinning meaning.
- Require the knowledge wide from end-user.
- If owning a few time and expense of.
- Observation.
1. How that method is used.
- Personally a analyst visit the perception location.
- Analyst record occurrence in perception location, including volume and processing of spread sheet.
2. Goals of method.
- Location process is geographically shown in DFD (Data Flow Diagram)
3. Advantage of method.
• Get the fact records than opinion.
• Don't require the question construction.
• Don't hellion or hide something (end-users don't know that are them perceived).
• Analyst don't base on the oral explanation from end-users.
4. Loss of method.
- If seen, analyst is possibly alter the operation (end-user feel to be perceived).
- On a long term, the fact obtained in one observation might not precisely (representative) daily in a condition weekly or.
- Require the experience and special expertise of analyst.
5. When is the method good to used.
- Require the quantitative picture be like time, volume etcetera.
- Suspicion that end-user tell a the occurrence be in fact don't happened (pretended).

Tip practical in doing the observation:
a. Don't perceive during old ones.
There are two reason, that is : with time old ones will in disorder operation which is is perceived, and will bias the problems be in fact.
b. Make the summarized note.
c. Before observation, advise to supervisor and user in concerned the things do would be done and why done, so that will lessen the trouble.
d. Use checklist the briefness concerning the information required with.
e. Don't do the observation without plan.
- Procedure Analysis.
1. How that method is used.
- With operating procedure can study and identify the document stream lock passing the information system, that is with data flow diagram (DFD).
- Every key document stream explain the system operating procedure.
- Through observation, analyst study reality than describe distribution volume (high, lower, medium) and what do is hereinafter done to copy of its genuine document.
2. Goals of method.
- Especial document in DFD (Data Flow Diagram)
- Process in DFD.
3. Advantage of method.
- Workable Procedure evaluation with interferences
- Minimum and don't influence the user operation.
- Stream procedure can become a structure checklist to do the observation.
4. Loss of method.
- Procedure might not complete and don't - up to date again.
- Study document stream schema require the time and membership of analyst.
5. When is the method good to used.
- Decide do problem failure of system can assist good scheme.
- Analyst team don't totalize familiar with document stream.
- Describe the document stream hellion activity of function.
- Document survey
1. How that method is used.
- Identify the especial document and report (physical data flow diagram).
- Collect the document copy actual and report.
- Each report or document, used to record data, cover the field ( type and measure), usage frequency and coding structure.
2. Goals of method.
- Data key stream shown in data flow diagram (DFD).
3. Advantage of method.
- Minimization interupt from his operational function.
- Start of data dictionary element.
- Oftentimes, can consider the fortunate modification procedural.
4. Loss of method.
- Require the enough time (there are natural business organization report and document floods).
5. When is the method good to used.
- Had to be done [by] if a system will designed (during activity of analysis, in clarifying design new system and document analysis can assist to determine the scheme duty hereinafter).

Sampling
Sampling can assist to lessen the expense and time. Require to careful to choose sample from population, so that require membership of statistic so that is not experiencing of threat or failure.

CONSTRAINT Resource:
• Time.
A anti system have to be phrased in framework since natural system of degradation of function swiftly. Constraint at the present time can influence the analyst to consider the technological innovation which is is impossible to be operated brief during. Therefore require to require the time enough so that have diffuseness of time so that can make the best alternative.
• Money.
Ideal information system will require the costly expense, so that require the enough financing. This matter there will be because happened emulation with his competitors where they inculcate the big investment in its information system.
• Expertise.
Staff information system might not have the enough experience or knowledge like telecommunications problem, database integration, and interactive setting. Company can contract the consultant to add design ability. This matter later will be given on to the released expense constraint for the energy of consultant.
• Technology.
Requirement of technology possibly will become the main problem in pick a back work the system, so that require to pay attention growth of continuous technology, which is his consequence happened expenditure of big expense and technology don't wearer of under developed from his competitors.
• Factor External.
Many incoming constraints from outside setting design, be like prevention use the exotic of technologies, prevent to look after the local data in a center database system, etcetera.



Document requirement of analysis:
- Analysis instruction: Relation with final user, perception of process, problem of data collecting.
- Requirement user: Actual requirement, report requirement, requirement of training and influence of new system.
- Constraint System: Explain the expense and time constraint, membership, technological and factor external.
- Document in the form of data collecting instrument, statistical consensus, data stream is in logical and physical, data element early in data dictionary.


GENERATING SYSTEMS ALTERNATIVES
How to draw near the system condition in this time with ideal system condition?
Make the alternative to solve problem the information system.
The best alternative is applied wise.

Choice Strategy
1) Distributed versus centralized processing
In this time, there is tendency happened change of decision of information from centralized data processing to decentralized end-user responsibility centers.
In environment process the distribution, end-user decide equipments, development priority and implementation.
In other shares there are growth of amount end-user which step into the computer world. They try the newest technology regardless of expense, and risk. Without membership, designer of system will stay in the conservative environment (fussy).
2) Integrated versus dispersed database
When organization use the database system spread over, designer of system have the consideration choice concerning file any kind of do the included in database and data any kind of do the entering in file. Integrated database handled by administrator the database look after all data controls storage, access and modification. Upstairs management decide as according to choice designer of system by paying attention the side amenity of his control.
3) Surround Strategy of System Development
Strategy system development is important because many companies have the heap (backlog) from new system which designed and condition of system which is is modified. This strategy permit designer of system use difference of programming language and run it [at] different computer to a system full compatibility (a totally compatible system). Environment around strategy is of vital importance in confiscation problem, where one company get possible and other company of its information system don't compatible with its (differ).


Tactics choice
Management decide now or later, change the modification opponent, and configuration SDLC. This election is done before operational choice.
Now or later
- Technology.
A technological breakthrough to needing consideration for a few years come.
- Cash flow.
Stream company cash condition require to to be considered in development or replacement of system.
- Resource membership.
In doing the system development require to to pay attention the good expert energies in concerned in his scheme and in his usage wait.
- Politic.
Many information systems is is in this time proposed by someone in company.
To one or more the reason of, information system department may choose to slow down the development or replacement of system.

Speed vs cost
Alternative information system is first time will be compared to quantitative usage expense. Hence designer has difficulty accommodate increase of speed in the form of cost-saving.

Choice concerning scheme of operational
Scheme choice grouped inside input, processing, and output.
Each group can have the choice as follows:
i. Input
1) On-Line versus off-line entry data.
Off-Line entry data don't have the ability good to validation transaction immediately. Therefore, on-line [of] entry data suggested is fixed used in information system configuration.
2) Keyed versus machine-readable entry data.
Machine-Readable entry data can improve speed, lessen mistake of inclusion of data, and cost effective for worker (save human costs). Anyway requiring the big investment in the case of equipments and its conservancy.
3) Centralized versus decentralized entry data.
Decentralized entry is quicker but his mistake level is high because many the users enter the data. Machine-Readable entry require inclusion of the decentralization give advantage of speed of process in catching the data source (point of sale).
ii. Processing
4) Batch versus real-time record update.
Batch processing cause the update record old, suited for centralized entry data. Real time processing require the equipments expense and boost up speed of process.
5) Sequential versus direct access to records.
Sequential access is relating to the batch processing.
Direct access relate to real-time processing.
6) Single versus multiple-user update of records.
A design system to multiple-user more complicated in security access and update record simultaneity. Complication happened the moment speed of process is important and his application with process - real time.
iii. Output
7) Traditional versus turnaround documents.
Traditional document is document of its data way to system through key input. Turnaround documents is data to system through machine reader of document.
8) Structured versus inquiry-based reports.
Structured report made in standard format and provided routine, is while inquiry-based reports made pursuant to request with format according to request of user. Often inquiry-base report found in environment real-time where data have to be accessed quickly.


Comparison tactics
System compared to pursuant to expense and advantage relatively. Expense is requirement of payment for designer and operation information system.
Advantage is assessing or additional condition as information system implementation result. The things including lessening the error rates, increased customer sales, and quicken the time respond. Advantage is difficult something that measured because having the character of qualitative (is not in the form of number only descriptive).
Improve satisfaction of consumer and lessen end-user resistance is advantage qualitative. Advantage is opportunity to improve advantage of company.
There is three way of one system (A) can more pre-eminent compared to the other system (B).
1. Have the expense which is low to be compared to B, and both system have [is] same advantage.
2. Have the expense which is low to be compared to B, and A also have the advantage more compared to B.
3. A and B have same expense, but A have the advantage more.

Some Methods Comparative System
There is the 4 method commonly use to compare two or more information system, that is:
• Break Even point Analyisis
• Payback Period
• Discounted PayBack period
• Internal Rate of Return

Category of is expense of
Basically the expense of divided into the category:
a. Hardware: mainframe, minicomputers, microcomputers, and peripheral equipment.
b. Software: systems, utility, and application software.
c. People: analysts, programmers, operators, data enter personnel, etcetera.
d. Supplies: paper, tapes, disk, etcetera.
e. Telecommunications: modem, local area network cabling, multiplexors, front-end processors, etcetera.
f. Physical site: irrigate conditioning, humidity control, security, etcetera.

Nature of costs
Compare the information system expense through life of system, projection analyst how many is change of expense for the future. To do so, there is three information system operating expenses model, that is:
a. Linear.
b. Exponential.
c. Step function.

Cost information system can just happened once and can also happened chronically.
Cost information system that happened once that is ontime cost and development cost that happened system development moment.
Expense information system that happened continually among its are reccuring cost and also operational cost where this expense happened the information system moment operate every day.

Factor Information system
Some factors is qualitative which instructing the good information system performance:
a. Lessen the mistake level (increased accuracy).
b. Lessen the time to improve mistake.
c. Lessen the time listen carefully from workstation interactive.
d. Quicken the ready time of report (information).
e. Improve system security.
f. Multiply the updates of source of record active.
g. Improve the user fasting.
Some the factors measurable, but don't in money.

Strategy company factor
Information system can make advantage in company. Improve advantage in this time any way is difficult to be estimated. Increase profit often times don't happened suddenly, but happened the some years after implementation of new system.
When two system alternative come near equality of comparison, open door to consider the company strategy factor.

There are the company strategy factors, that is:
1. Customer satisfaction.
An information system can cause carefulness submit the efficient desire and product [of] consumer. Improve satisfaction of consumer will no doubt improve the sale. Be like improvement of sale, any way difficult to be predicted and quantitative.
2. Increased sales.
System point of sales (POS) struck from depository of duties record. Management hope the sale staff faith full to time of effort marketing and this improve the sale. But sale will improve difficulty predicted in money.
3. Customer and vendor commitments.
Company is do design online system input and enable the direct consumer access to his system. Consumer is now locked (depended) at this system so that have commitment to be devoted (like) at the company. Commitment consumer and vendor difficult to be predicted.
4. Information product marketing.
Oftentimes, usable new information system by other company. Be like American Airline provide the product marketing information system during year of 1970, company develop a system ordering of ticket and then this marketing system is also used by other air transport service, so that become the beneficial product.


PRESENT PEMBELAJARAN SISTEM.
Do the presentation in a word but can explain all point in presentation items, so that hearer doesn't fell bored with long explanation.
Lessen explanation of technique in detail, this done because usually participant of presentation have known the usage of technique in general and remain to be explained why do using the mentioned and what is its benefit.
Present clearly by means of model assist visually, so that hearer can easier conceive what do is presented.
If using the model use the appliance assist for example. laptop so that more informative.
Emphasize advantage of information system proposal. with a few the alternatives according to natural by the condition of company.
No-go decision
Top management have to decide to continue (go) by developing the new information system or slow down or frown on the system development (no-go). If decision of upstairs management set mind on to develop the system, departmental [of] information system start process design (scheme) the next phase. If top management frown on the new information system proposal, hence systems development life cycle (SDLC) discontinued. Decision seldom simple as that. Often, top management find the problem with system study.
Serious insufficient problem cause the stop project, but they ask the reactivity (rework system study). This decision is basis for waterwall model of systems analysis. Model explain some repeated step shareses. Sometime, information system department make decision to repeat the step (repeat stages) before explaining (presenting) system study. With alternative, repeat a step SDLC before all or not to speak of with go / no-go decision. If top management agree development of new information system proposal, the next phase in SDLC is system design.

Friday, March 6, 2009

Common Review of System Development

Common Review of System Development
systems development
systems development is compose a new system to replace the system old ones as a whole or improve the system which have exist. Old system need to repair, if:
1. There are problems at the system, that is:
a. Irregularity at old system cause old system can’t operated accord who expected, that is:
- Insincerities intended cause doesn’t peaceful of estae properties of company and truth of data.
- Insincerities is not intended also cause truth of data not well guarantee.
- Inefficient of operation.
- Is not adhered by of policy of management which have been specified.
b. Growth of organization cause must compose new system, that is requirement of information is progressively wide, data-processing volume progressively mount, change of accountancy principle.
2. Obtain opportunities
Organization begin experience that information technology need to used for increase provide information until can support process taking decision which doing by management.
3. Directives
Compilation of system is also happened with existence of instructions the from the top leader or organizational from outside, example regulation of government.

Expectations after developing a system information.
- Performance
improvement of work before and after usage SI visible from many works able to be done and completion of task time mean, follow the example of before using SI a organization can only finish 3 unto 5 work in one day and need the old time for the data processing, but after using SI, organization can finish 10 unto 11 work and data processing have with quicker time.
- Information
improvement of the information quality obtained from data processing with SI, for example before using SI a organization doing many mistake of data-processing moment so that the quality of output crummy, after using SI mistake in data processing thus far decrease, so that the quality of information become nicer.
- Economy
SI (system information) can lower of expense, follow the example of before using SI data processing done by some people so that cost money to employ them, but with SI, enough one commisioned just employees for the input of just data is while the processing is system, so that more economical in giving the salary employees.
- Control
improvement to operation to detect and repair the insincerity and also mistakes and there will be happen. Example, system can process the more accurate data of human, system can become peacemaker of data in order not to can be accessed by people who have no business at company.
- Efficiency
SI easier do the data processing, example of swalayan have used barcode for the input of goods code to sales transaction moment computer.
- Services
SI also can give the service at society, for example transaction pass web making the people not necessarily come to selected shop for transaction.


Purpose of developing an system information
1) Resolve of problems
2) Reach for opportunities
3) Fulfill given instruction

Principle System Development
1. system made or developed have to can support the management, here a developer of system have to know how do management of the company so that the system made as according to requirement of company management. for example a company of bag order the sale system pass web, hence woke up system have to be made can do the payment pass no account, publicize the products, and can calculate the shoe type what do most saleable bought by customer, so that company can make the more product like that.
2. System is big investment
Each investment have to consider 2 matter following:
a. If the alternative is disregarded and have come too far unintentionally to inculcate the fund to a[n invesment project, hence investor will lose time to plant his fund to other invesment, thus here the investigation of good for investor to determine the project which give biggest advantage.
b. Best investigation have to valuable , best investigation just told profit if valuable with the meaning benefit (benefit) or result of reverse bigger than expense to obtain it (cost). cost-benefit analysis & cost-effectivenes analysis applicable to determine what is valuable invesment project good or don't
3. Developed system need educated people
developed system need the educated people [of] involver in development and usage of system is educated people concerning the problems and to the solutions is possibly done. educated [is] not meaning have to formally sit in high teacher, but can be done groundingly (on-job-training). core of someone have to have the education to be faced by his problem.
4. Step work
System development life cycle, first have to made scheduled for refer the steps work and duties to be done, so that process the system development can be done and completed on schedule with planned budget.
5. System development don't have to ordinal
Intention of statement is step work can be done at the same time because if project have ever been quicker hence can be done by the quicker, we can do examination so that can know insuffiency of project and improve it.
6. Don't fear to cancel project
If done project beyond question could give advantage clearly can be continued, but if project experiencing of many problem and have cannot to be developed to become the system able to fulfill requirement early hence this project have to be discontinued in order not to generate loss of larger ones again.
7. System documentation
Documentation must be done at the while process of system started, because communications materials documentation applicable to among system analysts with user of system and applicable to push involvement of user of system. Documentation is also function to note everything performed within making of system so that with documentation, easier system to be developed.

System development life cycle
Life cycle l by the system development is forming the used to depict the especial step and stages steps in the step in course of his development. There are three life cycle model, that is:
1) Waterfall Model

At waterfall model, first will enter the phase requirements when done by gathering of problems and requirement of system then analyse problems and requirement of the system. Then step into the phase design, where made design system of requirement analysis and problems of system, then step into the phase implementation, [at] this phase start to be made or implementation design system into a system, for example making or coding program with design program which have been made. After system is completed step into the phase verification, at this phase of system tested by do system have can finish all problems and fulfill requirement at phase requirements, if not yet hence system will improve at this phase, after have will step into the phase maintenance. This phase is conservancy phase, where can be added the functions at system so that can give the better system again from before system.

2) Iteratif Model
At iteratif model, first will be done initial planning to determine planning of making of system and determine will make what do system. then step into the phase requirements, here all problems and requirement of system to be made. Then at phase analysis & design to analyse problems and requirement [at] phase requirements then make design his system. [At] phase implementation start to be made by system from design the, then system will be tested [at] phase testing, if in rough will be noted [at] phase evaluate then return to the phase requirement to collect system insuffiency, then step into the phase analysis & design then step into the implementation phase again for the repair of system, so continue the system shall perfect, after have, system will be weared by deployment.
3) Spiral Model
Model Spiral is initially proposed by Boehm [BOEHM88]. Model spiral is modeling the software process evolution which stringing up the nature of iterative from model Iterative and nature of systematic of model waterfall.
This model contain six duty region:
Communications client: required duty to develop the effective communications among developers and client.
Planning: required duty to define the resource, accuracy of time, and other related information.
Risk analysis: required duty to appraise the good risk of management and technical.
Engineering: required duty to develop one or more represented from application.
Construction and launching: required duty for construction, to test, tide, and give the service to user.
Evaluation client: required duty to obtain feed back of client by made system evaluation.

• Planning
• Getting requirements  requirement and problems of system
• Project planning (based on initial reqs.)
• Project planning (based on customer eval.)
• Risk analysis
• Cost/Benefit and threats/opportunities analysis
• Based on initial reqs. and later on customer feedback
• Engineering
• Preview it
• Do it
• Customer evaluation

Approach of system development
a. Classic approach vs approach of structure.
Classic approach
Approach method is classical develop the system by following the steps in system life cycle without supplied by adequate techniques and appliance. Problems emerging with this approach is:
• Development of software become difficultly, because this approach [is] less giving [of] appliances and techniques in system development, so that process the development become difficult and not directional done.
• Expense become costlierly.
• Possibility of mistake of big system, because classic approach don't provide the way to examination system.
• Less well guaranted efficacy.
• Internal issue applying of system, because this approach don't entangle [user/ wearer] of system at the (time) of system development, sengingga [user/ wearer] don't know usage of system how to this.
Approach of structure
approach of structure provided with the techniques and appliances required in system development so that end result of developed to be system to be got by theX the is system [of] his structure is defined better and clearly.
this approach cover:
• Consumer involve from early to determine requirement of system.
• Use tools-tools be like data flow diagram.
b. Piecemeal approach vs systems approach.
Piecemeal approach is the system sill emphasize at an selected application or activity. This approach, selected to be application or activity to be developed regardless of his position in information system or regardless of target entirety of organization. This approach only paying attention activity or application is.
systems approach pay attention the information system as one unity integrated to each activity or his application. this approach also emphasize at the goal achievement to entire/all organization.
c. Bottom-up Approach vs top-down approach.
Bottom-up Approach started from level under organization, that is level operational where transaction done. this approach is started from formulation of requirement to handle the transaction and climb level to the by formulating requirement of information based on the transaction.
Top-down approach started from level to the, that is level planning of strategy. this approach is started by defining the target and policy of organization, hereinafter to analyse requirement of information. After analysis hence process will go down to transaction process that is determination output, input, data bases, procedures operate for and control.
d. Approach of system - totally vs approach moduler.
Approach of system is the approach develop the system at a time totally, This approach [is] less synchronized of complex money system, because will become difficult to be developed. this approach is distinguishing the classic approach.
Approach moduler is the system trying break the complicated system become some shares or module modestly, so that system will be more is easy to comprehended and developed, as a result system will be able to be developed on schedule which have been planned, is easy to comprehended by user of system and is easy to looked after. This approach is marking of approach of structure.
e. Great loop approach vs evolutionary approach
Great loop approach apply change totally simultaneously use the sophisticated technology. this change containing many risk, because quicker computer technology expand and to [be] yrs. to come have become worn out. this approach become costly enough, because this approach use all technologies and difficult to be developed.
Evolutionary approach apply the sophisticated technology just for just the applications need at that moment and will continue to be developed for the next period follow requirement according to growth existing technology. approach expand to cause the invesment don't too costly and can keep abreast of the technology quickly, so that used technology don't be worn out quickly.

Methodologies System Development
Methodologies is unity of methods, procedures, work concepts, the postulates and orders used by a[n science, artistic or other discipline.
Method is a way, systematic technique to do something. Sill system methodologies mean is methods, work concepts procedures, orders and postulates to be used to develop a[n information system. In system development of information, needed to use a[n methodologies able to be used as by guidance how do and what do had to be done [by] during development. By following the procedures or method given by a[n methodologies, hence development of system can expected will be able to be finished successfully. Is for that needed algorithm is procedure sequence for billows of problem.


Three classifications of development methodology
1. Functional Decomposition methodologies
This methodologies emphasize at resolving of system into subsystem-subsystem the smaller, so that will be more easy to be comprehended, designed and applied. Which included in this methodologies is:
- HIPO (Hierarchy plus Input-Process-Output).
- Stepwise refinement or Iterative stepwise refinement.
- Information-Hiding

2. Data-oriented methodologies
This methodologies emphasize at characteristic of data to be processed. This methodologies is grouped into 2 class:
• Data-flow oriented methodologies
this methodologies is in general based on resolving of system into modules pursuant to from the module logic behaviour and data element type in system. Which including this methodologies is:
- SADT (Structured Analysis an Design Techniques)
- Composite Design
- Structured Systems and analysis and Design (SSAD)
• Data structure oriented methodologies
this methodologies emphasize structure of input and output in system. Which including this methodologies is:
- JSD (Jakson’s systems development)
- W / O (Warnier / Orr).
3. Prescriptive Methodologies
Which including methodology is:
- ISDOS ( information system design and optimization system) usefulness from ISDOS is optimal process system development of information. ISDOS have two component, that is PSL and PSA. PSL is especial component from ISDOS, that is a Ianguage to note requirement of user in the form of machine-readable form. PSA is the software package looking like with data dictionary and used to check the entered data, which kept, which analysed and the yielded as output report.
- PLEXSYS. Utilizing It is to do transformation an statement Ianguage computer high level to a executable code to a[n hardware configuration which wanted.
- PRIDE, is a[n inwrought software which good to analysis or design structure system, data management, management of is project of and documentation.
- SDM/70, is a[n software contain with method corps, estimation, documentation and guide of administration to assist the user to develop and take care of the effective system.
- SPECTRUM, is developed system development methodologies and have some versions. SPECTRUM-1 (to life cycle conventional), SPECTRUM-2 ( for the system of management of is project of structure) and SPECTRUM-3 (to be on-line interactive estimator).

Appliance and Technique in System Development
System development appliances in form of graph are as follows:
a) HIPO diagram, used in methodologies HIPO and other methodologies.
b) Data flow diagram, used in methodologies structured systems analysis and design.
c) Structured chart, used in methodologies structured systems analysis and design.
d) SADT diagram, used in methodologies SADT.
e) Warnier/Orr diagram, used in methodologies Warnier/Orr.
f) Jakson’s diagram, used in methodologies Jackson System Development.

Appliance use the schema:
1) Activity Charting is schema to depict activity.
a) System flowchart
b) Program flowchart
- Program logic flowchart
- Detailed computer program flowchart
c) Paperwork flowchart is referred also from flowchart
d) Database relationship flowchart
e) Process flowchart
f) Gantt chart
2) Schema to depict to arrange situation (layout charting)
3) schema to depict personnel relationship (personal relationship charting)
a) Working distribution work
b) Organization chart
Technique System Development
a) Management technique of project of, that is CPM (Critical Path Method) and PERT (Program Evaluation and Review Technique). This technique is used in for schedule of project.
b) fact finding technique, is technique able to be used to collect the data and find the facts in activity study the system, that is:
- interview
- observation
- questionnaires
- sampling
c) cost-effectiveness analysis or cost-benefit analysis
d) Technique to run the meeting
e) Technique inspect / walkthrough


System Analyst and Programmer

System analyst: study problems and determine requirement of user of system to identify the resolving. Analyst system responsibility at system as a whole, knowledge of system analyst don't only at computer technology, but also at application area who handled by it. Work of analyst system entangle the relation many people, including system analyst humanity, programmer, but also user of system and manager.

Programmer: write the program code pursuant to designing to wake up the made by the Analyst system analyst on call link difference of knowledge that happened between users of system and Programmer. Responsibility limited to making of computer program, knowledge only limited to computer technology, computer system, utilities and needed programming language. Work don't concerning the relation with many people, enough only programmer and analyst.

Knowledge to be owned by system analyst:

1) Knowledge and membership concerning data-processing technique, computer technology and program computer.
a. Technical membership to be owned [by] is membership in usage of appliance and technique for the development of software of application and also membership in using the computer.
b. Technical knowledge to be owned cover the knowledge concerning hardware [of] computer, technological [of] data communications, computer Ianguages, operating system, utilities and other software packages.
2) Knowledge of business in general, this knowledge is required so that system analyst can communicate with user of system. Knowledge of business cover the financial accounting, cost accounting, accounting management, system operation of management, marketing, production, personnel management, finance, organization behaviour, company wisdom and others.
3) Development of Quantitative Method, many in developing the application models, for example linear of programming, dynamic programming, regresion and others.
4) Membership of trouble-shooting, is ability to be able to break problems of faced by complex of business into parts of his, analyse it and then have to string up it again become a system so that can overcome the problems.
5) Membership of Communications between Personnel, this membership is needed in interview, presentation, meeting and making of reports.
6) Membership in constructing the relation in personnel.