Week 7
Mei 2, 2009

1. no cardinality between PART and PROJECT
2. Ternary relation between TANGGUNGAN and PROJECT

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
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 nonkey attribute functionally determined by another nonkey attribute ( or by a set of nonkey attributes). That is, there should be no transitive dependency of a non key primary key.
Week 6
April 25, 2009
DATABASE NORMALIZATION
Database design process (review):
- Gather user needs / business
- Develop a needs-based ER Model user / business
- Convert E-R model to the set of relations –> tables in database
- Normalisasikan relations, to remove anomalies
- Implemented to create a database with a table for each relationship that is normalization
Baca entri selengkapnya »
Week 5
April 19, 2009
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)
Manufacturing companies -> data production planning, actual production data, data ordering materials, etc.
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
Size in Database
Bit -> data is the smallest that contains the value 0 or 1
Bytes -> the set of bit-bit similar
Field -> byte-byte set of similar, in the database used the term attribute
Field / Attribute
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
Attribute Type :
- Single vs Multivalue
Single -> can only be filled at most one value
Multivalue -> can be filled with more than one value with the same type
- Atomic vs Composit
Atomic -> can not be divided into the attributes of smaller
Composition -> is a combination of several attributes of a smaller
- Derived attribute
attribute value can be derived from other attribute values, eg, -> age resulting from the date of birth attribute
- 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 categorized as follows:
- Master File
- Transaction File
- File Report
- File History
- File Protection
- Job File
Domain
Domain is the set of values that are allowed to reside in one or more attributes.
Each attribute in a relational database is defined as a domain
Key Element
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.
Key Type :
- Superkey
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 superkey)
- Candidate 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 superkey 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 unique
- 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 cardinality 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.
Entity Relationship Diagram (ERD)
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
ERD’s Elements :
- Entity
In the ER Diagram Entity is described with the form of a rectangle. Rntity 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 their relationship.
- 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
- Cardinality
tuple indicates the maximum number that can be related with entities on the other entity
Relationship Degree :
- 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.
There are 3 cardinality 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 .For an incident on the first entity can have any relationship with many incident on the second entity, if the one incident on the entity the second can only have one relationship with the incident on the first entity.
- Many To Many: if any incident occurs in an entity many have relationships with other entities in the incident.
week 4
April 4, 2009
Data Flow Diagram Also called DFD
DFD goal :
- Describes the distribution of the modules to a smaller point of view
- Easier for users with less understanding to understand the field of computer systems that will be done
Week 3
Maret 27, 2009
Initial Observation and Needs Analisys
Why we need Initial Observation and Need Analisys? There are some reasons :
1.Gap difference between the purpose of the system and actual system conditions
2. Reports detection problem is not really real , i.e :
- Too ideal destination
- Lack of resources and / or attitude
- Measurement system is less accurate
- System that is the purpose behind
- The difference between the system and the iddle system
Week 2
Maret 7, 2009
This is all about our classes in information and system design from week 3..continue from Week 1 post..
Before we start to build and develop an information system, we need to know the reasons need to be done so that the development of a system. Here are some reasons for the development of a system :
Week 1
Februari 20, 2009
Wuihh..gila rek..hampir 2 tahun gak nulis blog..untung sik aktif ni blog..:D
Sik..sik sekarang ini mesti pake bahasa inggris ngblognya..:D
Oke..oke jadi kita akan mulai pake bahasa inggris.., Jadi saat ini kita akan membahas tentang ADSI…”eit..eit mas..kok pake bahasa indonesia?”…hehehe
Ok…now start writing in english..:D
Let us start about ADSI..!
Do you know what is ADSI?..wekekeke..That is funny acronym if we remove the “D”..:D
Yes..right..ADSI is acronym from Analisis dan Desain Sistem Informasi..one of more course that I was take..
Kemajuan Indonesia di bidang komunikasi
April 5, 2008
Tiga negara, yaitu Amerika, Inggris, dan Indonesia berlomba-lomba menentukan siapa diantara mereka yang lebih dulu menggunakan teknologi
canggih dengan meneliti keadaan tanah negaranya masing-masing untuk melihat siapa yang terhebat di masa yang lalu.
Disepakati penelitian dimulai dari Amerika trus Inggris & terakhir Indonesia.
Di Amerika, stl penggalian sudah mencapai 1000 meter maka ditemukan kabel tembaga, maka Team Amerika dengan banggannya menyimpulkan
bahwa 1500 tahun yang lalu telah dibangun jalur telepon dengan memakai tembaga di Amerika.
Di Inggris, setelah penggalian sudah mencapai kedalaman 1000 m tidak ditemukan kabel tembaga, tetapi setelah mencapai kedalaman 1500 m ditemukan serpihan kaca maka Team Inggris tersebut dengan bangganya menyimpulkan bahwa 2500 tahun yang lalu telah dibangun jalur komunikasi dengan memakai Fiber Optik di Inggris
Dan terakhir di Indonesia, setelah penggalian sudah mencapai kedalaman 500 m dan 1000 m sampai seterusnya tidak ditemukan apa-apa, lalu dgn sangat bangganya, maka Team Indonesia menyimpulkan bahwa 5000 tahun yang lalu komunikasi di sini telah menggunakan wireles.
Mlaku-mlaku neng trawas…rekkk..
Nopember 28, 2007
Algoritma Mencari Bilangan Prima
Nopember 27, 2007
Pertama..tama yang akan kita lakukan adalah lari keliling lapangan 3x sambil nyebut namaku….wekekeke…gak dhing…! Oke bilangan prima adalah bilangan yang habis dibagi dengan satu dan dirinya sendiri…..Oks..dapet kata kuncinya….
misal 5 :
5 mod 1 = 0
5 mod 2 = 1
5 mod 3 = 2
5 mod 4 = 1
5 mod 5 = 0
Nah..dari step-step di atas keliatan kan caranya…,dapat diambil kesimpulan kalo 5 itu bilangan prima…
nah jadi bisa kita mulai algoritmanya…
pertama
inisialisasi variabel
i ,prima dan bilangan yang akan diinputkan : bil
kemudian mulai
print(masukkan bilangan
baca(bil)
dari i = 2 sampai i = bil-1 lakukan
prima = bil mod i
jika prima=0 maka stop perulangan dan printf(bilangan bukan prima)
end perulangan
jika prima tidak = 0 maka print (bilangan prima)
selesai
Mas..mas..mas..kalo saya masukin 2 ato 1 ato 0 gimana?????
Tenang..tenang….Nah yang jadi masalah kalo dimasukkin angka dibawah 2…dibuat aja error handling di atas,kalo bilangan yang diinputkan kurang dari 3 maka jika 2 tulis prima selain itu tulis input bilangan salah…beres kan….
