Understanding And Various Kinds of Computer Network Topology

Definition of computer network topology is a method or concept for connecting several or many computers at once into an interconnected network. And any kind of computer network topology will differ in terms of data transfer speed, cost of manufacture, as well as its ease of maintenance processes. As well as any type of computer network topology has advantages and disadvantages of each. There are various topologies such as ring topology, star, bus, mesh, and the tree that will be discussed in the blog to learn this computer.


Various Kinds of Computer Network Topology

1. Topology Ring

In the ring topology each computer is connected to another computer, and so on until returning again to the computer first, and form a circle so called ring, this topology communicate using the data token to control access rights computers to receive data, for example, the computer 1 will send the file to the computer 4 , then the data will pass through the computer 2 and 3 to be received by the computer 4, so a computer will continue sending data if the destination is not the IP address him.

The advantages of computer network topology ring is in the process of installation and ease of installation, use a little amount lan cables thus saving costs.
The most fatal shortcoming of this topology is, if one of the computers or its cable problem, then the data transmission will be interrupted even error.


2. Bus Topology
Computer network topology bus neatly arranged like a queue and use only one coaxial cable and each computer connected to the cable using BNC connectors, and both ends of the coaxial cable must be terminated by a terminator.

The advantages of the bus is almost the same as the ring, the cable used is not much and saves installation costs.
Shortage of bus topology is that if there is interference or problems on one computer can interfere with other computer networks, and this topology is very difficult to detect disturbances, frequent occurrence of data queue, and if the distance is too far to be using a repeater.


3. Star Topology
This topology is formed like a star because all computers connected to a hub or switch with UTP cable, so that the hub / switch was the center of the network and served to control data traffic, so if the computer 1 wants to send data to the computer 4, the data will be sent to switch and immediately send it to the destination computer without passing through another computer. Computer network topology is the most widely used today because of its advantages more.

The advantages of this topology is very easy to detect which computer is broken, it is easy to perform addition or subtraction without disturbing the other computer, as well as the security level of the data higher.
The drawback of this computer is the network topology, requires a high cost for installation, as it requires a lot of cables and switches / hubs and network stability is highly dependent on the central terminal, so that if a switch / hub impaired, then the entire network will be disrupted.

4. Mesh Topology
In this topology each computer will be connected to another computer in the network using a single cable, so the data transmission process will directly reach the destination computer without going through another computer or a switch or hub.

The surplus is the shipping process faster and without going through another computer, if one of the computers were damaged will not interfere with other computers.
Disadvantages of this topology is clear, it will take very many costs because it requires a huge amount of cable and each computer must have a Port I / O that many, but it is very complicated installation process. 

5. Topology Tree
Computer network topology Tree is a combination of several star topology that connecting it to the bus topology, so any star topology will be connected to a star topology the other using a bus topology, usually in this topology, there are several levels of networks, and the networks are at a higher level can control networks that are at a lower level.

Excess tree topology is easy to find a fault and also easily make changes to the network if necessary.
Its shortcoming is using a lot of wiring, frequent collisions and slow, if something goes wrong on the network level is high, then low-level network will be disrupted as well.
There's more topology that I have not discussed above, but here are some frequently used topology, choose the topology that suits your needs and hopefully this article helps you, bye.

Steps - steps JAVA run in CMD

Steps - steps JAVA run in CMD
1. Before running java on the CMD that the first thing you should do is to install JDK
2. After you install JDK JDK address setting on the patch, follow the steps - these steps on the way of setting the address JDK patch
3. Click >> Computer >> proporties
4. Click the Advanced System Settings >>
5. Click >> Environment Variables
6. Locate and then click Edit Patch >> >> In awalii semicolon and then copy the address JDK from system C, step - a step to copy the address JDK you can follow on this beriku explanation:
7. How to copy JDK address in system C, click >> Local disck (C), then click >> Program Files
8. Then click >> Java
9. Click >> jdk
10. Click >> bin
11. Copy JDK then enter the address in Patch (Prior paste type a semicolon terlebi patch first)
12. Sign in CMD, now you can menjalangkan java on CMD, you first create java script in notepad make sure the class name match the name on the deposit at the end with a point java examples (nama_file.java) and run as shown below:
13. Here's an example of a simple Java program on a notepad:
public class try
{
public static void main (String [] args) {
System.out.print ("try");
}
}
14. Here's an example of how to run a Java program in CMD and explanation, press Windows + R, then enter the following command: D: (for incoming kepartisi where where you store your java file), dir (to display a list - a list of files to determine whether the file java you are already there), then javac nama_file.java (for konfile your java file), java filename (to run the program).

Object Oriented Programming

What the PBO?

          OOP / PBO is a programming paradigm that is popular today that has replaced the procedure-based programming techniques. Object Oriented Programming which also means Object-oriented programming has been discovered around 1960 and was developed in the early 1970s.

Object-Oriented Programming (Object Oriented Programming / OOP) is the object-oriented programming, where all the data and functions are wrapped in classes or objects. Each object can receive messages, process data, sending, storing and manipulating data. Some objects interact with each other to provide information to one another.
          Each object must contain information about itself and can be connected with another object. Object-oriented programming is different from procedural programming using only one page down to do a lot of commands or statements. The use of object-oriented programming is very benyak once, for example: java, php, perl, C #, COBOL, and others.

          In the Object Oriented Programming concept known some common terms, namely:

- Attribute

Attribute Definition and Overview

           The attributes of a class is a global variable that is owned by a class, an attribute may have the right to access private, public or protected.
An attribute that is declared as private may only be accessed directly by the class wraps, while other classes can not access these attributes directly.

           An attribute that is declared as public can be accessed directly by other classes outside the classroom are wrapped.
An attribute that is declared as protected can not be accessed directly by other classes outside the classroom are wrapped, except that access class is a subclass of class wrapping.
           Attributes are also commonly called state / properties / fields is part owned by a class that does not do surgery, but her surgery is performed so as to change the value of the attribute.

Characteristics Attributes

          In class, the attribute referred to as a variable. Attributes can differentiate between one object with another object. For example, in the class: the students, the students are the object A and object of the student B.
          The only difference between the A and the object B is its NPM (student identification number) that is an attribute of the object. In the attributes, there are also two variable term, namely Class Instance Variables and Variable.
Where each variable has its own characteristics, including:
In the Instance Variables instance à each object has its own variables and store values.

          While the Class Variables à attributes shared by all objects that come from the same class, as well as all objects have the same value of the variable class. attributes of the object of the same class.

- Method

Method Definitions and Overview

          Method is a function or procedure that is created by a programmer in a Class. In other words, the method in a class similar in function or procedure in procedural programming.
          On a method in a class also have access permissions as well as the attributes of the class, the access permissions that include private, public and protected who has the same meaning to permit access to the attributes that have been discussed previously. A class may have more than one method with the same name as long as it has a different input parameters so that the compiler or interpreter can recognize where the method is invoked.

          This is called overloading. In a classroom, there is also the so-called static methods or attributes that have the keyword static. The purpose of the static here is a method that can be accessed to share with all other objects without having to create an object which has a static method before (without the new), but a static method has limitations that can only access attributes or other methods in the class that wrap which is also static. Static method is usually implemented for the main method.

Characteristic Method

          Within a class, the behavior is stored in the form of Method. Method is a series of statements / commands (command = line program) in a class that handles a specific task. Method are things that can be done by objects of a class.
Method is defined in the class but invoked through the object. Method has a role include:
- Change the value attribute of an object,
- Receives information from other objects, and
- Send information to another object to perform a task (how objects communicate with another object is to use the method).

- Class

          Is a model that contains a set of attributes and methods in a unit for a particular purpose. For example, humans have the class attribute weight, height, age and then have a method to eat, drink, sleep. Methods in a class can change the attributes possessed by the class. A class is the basis of modularity and structures in object oriented programming.

Definitions and Overview Class

          Class is defined as a blueprint (plan), or prototype, which defines the variables and methods common to all objects of a certain type n (n means a certain amount). A class resembles a structure that is the data type itself, eg point data type that consists of x and y coordinates. Java language has been used a class to declare the type of data point because the Java programming language is a pure object-oriented programming language that does not know the structure, but to know what is called a class.

          Difference in a classroom with a structure is a class can stand alone and can be used for various purposes other classes, whereas a structure can not stand alone. A more flexible classes to be used by another class without having to disassemble the code of the main program, whereas if it is used, the structure must be demolished transform program code copied parts of the structure to another main program code.

          A file can consist of a variety of classes, but usually in the Java programming language file consists of only one class that is stored with the class name, eg List.java file containing the class list. However, if the class is made for example nama_kelas public class, then that class should be stored in a single file for one class only. After compiling then on there will be a Java .class file that contains bytecode of any class.

          If a file consists of two classes, then after compilation will produce the two .class files which will be read by the Java interpreter when the program is executed. A class when the program is executed and the new command is executed, it will be made an object. Class is a template for the creation of objects. Class also has members, including: the attributes and methods.
Understanding of brevity:
• Class is a pattern / template that describes a collection of objects that have similar properties and behavior.
• Class is a data structure of the object (the blueprint of an object), and the process of making an object of a class is also called instantiation.
• Class is the definition of data and functionality of a thing (object, concept, etc.).
• In the class declared variables and method owned by object

Characteristics Class

          Class has several characteristics, including: members of the class consists of attributes and methods. Each member class has its own access control, the point is whether the members of the class can be accessed freely (with the type of public) or only accessible through an interface.
          In this case, the interface is a device used for communication between different objects that do not have any relationship. Interface can be regarded as the communication protocol between the object.

- Object

          Is the embodiment of class, every object will have the attributes and methods that are owned by his class, for example: amir, Ahmad, minister to an object of class man. Each object can interact with other objects in spite of coming from a different class.

Object Definition and Overview

          Object is something that has an identity (name), generally also have data about himself or another object and have the ability to do something and be able to work together with other objects. Basically all objects in the world can be regarded as an object. Houses, cars, motorcycles, desks, and computers are examples of objects that exist in the real world. Object is the implementation class. In simple, it can be said to consist of properties (attributes) and methods.
Understanding of brevity:
• The object is a special object that is used to access members of the object (attribute or method) of the object itself.
• If there are other variables that have the same name as the name attribute inside the object, "this" can be used to refer to object attributes.

Object Characteristics

          Each object has two main characteristics, namely its attributes and behavior. A status object attributes and behavior is the behavior of the object.
          A simple example is the bicycle. Bicycle object has attributes: pedals, wheels, and gears, speed as well as having behavior such as runway and brakes. Just like the depiction in the real world, the development of programs with OOP concept also uses an object model that will store in a variable attributes and behavior in the methods or functions / procedures. The description:
Object instance: Bicycles
- Bicycles have attributes (state): pedals, wheels, spokes, and color.
- Bicycles have behavior (behavior): ascending speed, the speed decreases, and the gearshift bicycle.
In object-oriented software development, object in the software will store their state in a variable and store information behavior (behavior) in those methods or functions / procedures.

Concepts in OOP / PBO:

- Abstraction

          Is a way to look at an object in a simpler form. For example, we did not see a car as thousands of electronic components, mechanical systems with four tires, seats, steering wheel and so on. By Abstraction, a complex system can be viewed as a collection of subsystems that more simple, like a car is a system consisting of various subsystems, such as steering subsystem, subsystem braking and so on.

          Abstraction is the ability of a program to bypass aspects of information processed by it, namely the ability to focus on the core. Every object in the system serves as a model of the "perpetrators" abstract that can do the work, reports and changes in circumstances, and communicate with other objects in the system, without revealing how this excess is applied.
          Processes, functions or methods can also be made abstract, and some of the techniques used to develop a pengabstrakan.

- Encapsulation

          Is a mechanism to hide or protect a process from possible external interference or abuse of the system and also simplifies use of the system.
          Ensure the user an object can not change the state of an object in a way that is not feasible. Only methods in such objects are given permission to access the situation. Each object access interface that specifies how other objects can interact with it. Other objects will not know and rely on the representation of the object.

- Inheritance

          An attribute inherited concepts and methods that are owned by a class to class derivatives. With this draft class who made quite define specific attributes and methods therein, while the attribute and the more common method will be obtained from the parent class.
          Adjusting polymorphism and encapsulation by allowing the object is defined and created with a special type of object that has been ada.Objek-object can divide (and extend) their behavior without emotion implement the behavior of the (language-based objects do not always have inheritas.)

- Polymorphism

          Is a concept which enables the use of an interface similar to govern an object in order to perform an act that may in principle be the same but different.
Called object-oriented data model can provide more flexibility, ease of changing programs and is widely used in large-scale software engineering. Furthermore, supporters of OOP claim that OOP is easier to learn for beginners compared with previous approaches besides OOP approach easier to develop and maintain.
          Polymorphism via messaging. Does not depend on calling subroutines, object oriented language can send messages, some methods of dealing with a messaging depends on the specific object in which the message is sent.

          For example, if a bird receive "fast motion", he will move his wings and fly. When the lion received the same message, he would move his feet and ran. They said a similar message, but in accordance with the ability of these animals. This is called polymorphism as a variable in the program tungal can hold different types of objects while the program is running, and the text of the same program can call several different methods at different times in the same calling. This is contrary to achieve polymorphism functional language through the use of first-class functions.

understanding of accounting, financial accounting, management accounting as well as the importance of accounting

Definition of "Accounting",
"Financial Accounting" and
"Managerial accounting"

Definition of accounting, financial accounting and management accounting is indeed very different, it can be said that the definition of a cycle or chains are interconnected with each other that can not be separated. Financial accounting in the hospital in order to finance a hospital to run smoothly then the cycle is to be run properly.

As the initial process, must first know the definition of accounting, financial accounting and management accounting properly, so that will help achieve a satisfactory understanding.

1. Definition of accounting Accounting is the process of recording, calculating, identifying, measuring and release economic information in an agency / company so that it is possible
the judgments and decisions clearly and firmly for those who use the information. Effective use of accounting would be one way of doing effective financial management.

2. Definition of financial accounting Financial accounting is accounting which mainly produces information in the form of financial statements aimed at external parties, such as taxes, shareholders, and others. Examples of financial statements are: 1. Balance Sheet 2. Income Statement 3. Statement of changes in capital

3. Definition of management accounting Management accounting is the financial statements prepared primarily to generate useful information for effective decision-making by management for planning and controlling operations and perhitunagn costs.
Examples:
1. Revenue per service activities
2. Report of accounts receivable, cash reports and so on

"At first glance understanding of accounting, keunangan accounting and management accounting, may be
useful. "


THE IMPORTANCE OF ACCOUNTING

Throughout the economy of using money (Money) as a means of payment, the role of accounting is always crucial because the accounting record business events m \ a financial nature. Merchandise sales, payroll, and credit purchases are examples of events

recorded business accounting.

In various activities of our lives depend on the reliability of accounting. For example, when we perform retrieval cash at ATMs (automatic teller machines) then we actually ordered the bank do the accounting records. The cash withdrawal led to reduced cash in the bank, and we are in a bank account balances are also reduced by the value of the rupiah that we mentioned., What happens if the bank reduces the balance of our account more than the amounts of money that we receive? We would ask those problems to the bank, and immediately close the accounts

us because it reflects that the bank accounting unreliable. Accounting for government organizations to prevent and detect crime of corruption or misuse of public money. criminals do not want to accept bribes [bank transfer because the event will be recorded in the accounting of banks which became the eradication of corruption are easy to trace the flow of funds to corruption. Business organizations called companies even use accounting as a language to facilitate operations, making business decisions, as well as to account for the implementation of the task manager. Accounting is also commonly used to compare the performance of a company with other companies. The company therefore used as the language of business accounting (Accounting is the business language). in a word, accounting for no where where and useful in everyday life, both for individuals and for organizations.

How to fix the flash

Useful article this time is set way in the repair of damaged flash either from her or from the device software. Flash problem was manifold, when talking with the technicians then we will know where the damage. but when talking with people who despise looking for tutorials on the internet like me, then the damage will not be so obvious, that right is not it?

therefore I suggest you to try the following methods before deciding to buy a new flash (calculated saving money)
* HOW TO FIRST The first way is the easiest way to use CMD. usually potent if the damage is only corrupt or badsector errors in flash software.
 1. Open CMD. (click Start - Run - type cmd - press ENTER)
 2. Plug the flash that is broken,
 3. type FORMAT H: / FS: FAT then ENTER.
H is the location of your flash, if the location of the flash in the explorer is G then FORMAT G: / FS: FAT then ENTER.

* HOW TO BOTH still using the CMD. But there is little difference, which is merely check
 1. Open CMD. (the same way as above)
 2. Plug the flash that is broken,
 3. type CHKDSK / f H: then ENTER
 4. Press Enter until the check is completed.

* HOW TO THIRD-use features of Windows Check Disk
1. Plug the flash and then open Windows Explorer
2. Right-click the stick - Properties - Tools - Check Now
3. Check that there is a second option. "Automatically fix file system errors" and "Recovery of bad sectors"
4. Wait until the process is complete.

* HOW TO FOURTH using the Computer Management
 1. Plug the flash damaged
2. enter RUN then type compmgmt.msc - ENTER
3. Click on Storage and select Disk Management
4. If no flash is detected, right-click - Create Partition. then right click again - FORMAT

 * HOW TO FIFTH your flash seems fairly yuk damage directly to more extreme ways
1. Plug the flash
2. Download the software called HDDGURU Low Level Format
3. Install the program, then "Run As Administrator" for Windows Vista / 7/8.
4. Select the type of USB and then Continue.
5. After low-level formatting is complete, you can reformat the flash with the way the format as usual.

* HOW TO SIXTH using the HP Drive Key Boot Utility Quick Format
1. Plug the flash
2. Download the software called HP Drive Key Boot Utility
3. Install the software (Windows XP only)
4. Run the program - Select the type of FAT / FAT32.
5. Select QUICK FORMAT - Create New or Replace Existing Configuration.

*HOW TO SEVENTH by searching software from vendors using idVendor and idProduct
1. Download a software called USB Device Viewer
2. Plug the flash drive
3. Run the program (Run As Administrator for Windows 7 / Vista / 8)
4. Will be detected all connected devices, such as the mouse, modem etc. To make sure, select USB mass Storage. Unplug and re-enter.

5. Record idVendor and idProduct. in this case, I noted (idVendor: 0951) and (idProduct: 1624) 6. Go to this address >>> http://flashboot.ru/iflash/ 

7. Put idVendor to idProduct to VID and PID - click ENTER

8. It would appear some results, please Browsing Tools that I put a red mark as shown below

9. google search results directly leads to the official website KINGSTON

10. Open the link and I was immediately taken on a software utility that is specific to the IC flash repair damaged / corrupt / the error.

11. Download the software and use as needed.

* until here good luck, any kind of damage caused by the fault is not the responsibility of the author. Dare to try is the initial capital to solve a problem

Crimping way UTP cable to the RJ-45 (Straight and Cross)

Crimping way to RJ45 UTP cable (Straight and Cross). After learning Various Computer Network Cable Lan, we will do the crimping of the UTP cable using RJ-45 connectors that can be used to connect the computer hardware.

nah, before we start, the materials to be prepared is utp cable, RJ-45 connectors and crimping pliers and better if you if there is Lan Tester to test the cable, if not, still can use other ways to test her.

TANG CRIMPING

KABEL UTP

LAN TASTER

RJ-45

UTP cable consists of two types, namely Straight and Cross, a straight cable is used to connect two different hardware such as connecting a PC to the Switch / Hub, and Cross cable is used to connect two pieces of the same hardware as from PC to PC, Laptop to Laptop .Cara crimping UTP cable to the RJ-45.

To make Straight cable, the arrangement of the colors used are:

The composition of colors on the tip 1 = White Orange, Orange, White, Green, Blue, White Blue, Green, White Chocolate, Chocolate

Arrangement of the same color on the tip end 2 1

To create a Cross cable, the arrangement of the colors used are:

The composition of colors on the tip 1 = White Orange, Orange, White, Green, Blue, White Blue, Green, White Chocolate, Chocolate

The composition of colors on the tip 2 is = White Green, Green, White Orange, Blue, White Blue, Orange, White Chocolate, Chocolate How crimping UTP cable to RG-45

STEP STEP STRAIGHT AND CROSS CABLE CRIMPING.

Crimping way UTP cable to the RJ-45

1. Peel the skin of wiring width of 2 cm.

2. Arrange neatly contained within the eight wires in accordance with drawings and explanations above.

3. Align the cables are still tangled.

4. Flatten the end of the cable by cutting it using crimping pliers.

5. After making sure the correct color sequence and the ends of the cables are flat, the input cable into the RJ-45 connector, make sure the cable ends to touch the tip of the RJ-45, and jepitlah use crimping pliers.

6. After completing both ends of the cable, using the test Lan tester, if all the lights are on, it means that the cable has been in the crimping properly and can be used.

Database Design

preliminary

In this paper will discuss the stages in the design database. On the database that is used by a single user or a few users only, the database design is not difficult.

But if the size of the database that is medium or large database design will be very complex. Therefore, users expect the use of a database such that the system must be able to meet the needs of all the users. Of course, that these needs can be served well then it should be done anyway good database design, activities, what is being done at that stage.

Database Design goals

To meet the information comprising user needs specifically and applications - applications.

Facilitate understanding of the structure of information.

Supporting the needs of processing and some objects appearance (response time, processing time, and storeage space).

Database Design Process

Database design process consists of six stages:

Phase 1 Data collection and analysis

Phase 2, the database design is conceptually

Phase 3, Election DBMS

Stage 4, logical database design (model data mapping)

Stage 5, the physical design of the database

Stage 6 Database System Implementation

In particular the design process contains two parallel activities:

Activities that involve the design of the data content and structure of the database,

Activity on the design database processing and applications software.

On the other hand, we usually determine the design of database applications with led to the construction of a database schema that has been determined for the first activity.

6 steps above was not to be processed sequentially. In the phase 1 is a collection of information related to the use of the database. Stage 6 is implementing its database.

Stage 1 and 6 sometimes is not part of the design database. While that is the core of the database design process is at the stage of 2, 4, 5.

Phase 1 - Data collection and analysis

It is a stage where we make the process of identification and analysis needs and data is called data collection and analysis. To determine the needs of a database system, we need to know in advance the other parts of the information system that will interact with the database system, including existing users and the new useryang and their applications. The needs of users and applications is then collected and analyzed.

The following are the activities of data collection and analysis:

Define groups of users and fields of application

A review of existing documentation

Analysis of the operating environment and data processing

The list of questions and interview

Phase 2, the database design is conceptually

At this stage will be generated conceptual schema for the database that depend on a specific DBMS. Often using a high-level of data modelseperti ER / EER modelselama this stage. In the conceptual schema, we must specify databaseyang known applications and transactions mungkin.Tahap databasesecara conceptual design has two parallel activities:

Designing a conceptual scheme

Examine the needs of data from a database that is the result of phase 1 and produce a conceptual database schema in a DBMS-independent high-level data model as EER (Enhanced Entity Relationship) model.Untuk produce such schemes can be generated by merging various user needs and directly create the database schema or by designing schemes apart from the needs of each user and then combining these schemes. The data model used in the design of conceptual scheme is DBMS-independent and the next step is to choose a DBMS to do the design.

Designing transactions

Testing applications databasedimana her needs have been analyzed in phase 1, and generating details of transactions ini.Kegunaan this stage are processed in parallel along tahapp conceptual schema design is to design the characteristics of database transactions that have been known at a DBMS- independent. These transactions will be used to process and manipulate databases such time as the database is implemented.

Phase 3, Election DBMS

Selection databaseditentukan by several factors, including factors engineering, economics, and politics organisasi.Contoh technical factors:

The existence of DBMS in performing its duties as the types DBMS (relational, network, hierarchical, etc.), storage structures and access points that support DBMS, users, and others-lain.Faktor-economic and organizational factors that affect each Another in the selection of DBMS:

Data Structure

If the data stored in the database following the hierarchical structure, it is a kind of hierarchy of the DBMS should be considered.

Personal who has been accustomed to a system

If the programmer staff in an organization are familiar with a DBMS, then this can reduce training costs and time to learn.

Availability of the service seller

The existence of the seller service facilities are needed to help solve some of the problems of the system.

Stage 4, logical database design (model data mapping)

The next stage is to create a conceptual schema and the external schemas in the data model of the DBMS chosen. This phase is done by mapping the conceptual schema and the external schemas generated in stage 2. At this stage, the conceptual schema is transformed from high-level data model used in phase 2 into the data model of the data model of the DBMS chosen at this stage of the 3.Pemetaan can be processed in two levels:

Mapping system-independent

Mapping to the DBMS data model without considering the characteristics or special things that apply to the DBMS implementation of the data model.

Adjusting the scheme to the specific DBMS

Set the schema generated in step 1 to be adapted to the specific implementation in the future of a data model used on the DBMS dipilih.Hasil of this stage wearing commands DDL (Data Definition Language) language chosen DBMS that determines level of conceptual and external schema of the database system. But 10 in some cases, DDL commands to enter parameters so that the physical design of a complete DDL had to wait until the design phase has been lengkap.Tahap physical databasesecara can be started after the election of an implementation data model while waiting specific DBMS will be selected. Example: if it decides to use some relational DBMS, but has yet to decide a primary relationship. The design of the external schemas for specific applications can often be completed during this process.

Stage 5, the physical design of the database

Physical database design is the process of selecting the storage structures and access paths to the files database for achieving the best performances in various aplikasi.Selama this phase, designed the specifications for the database stored associated with storage structures physical, placement record and access points. Related to the internal schema (the term 3-level architecture of DBMS) .Some guidance in selecting the design of the physical databasesecara:

Response time

The elapsed time of a transaction database that is proposed to carry out a response. The main influence on the response time is under the supervision of the DBMS are: database access time to a data item designated by a transaction. Response time is also affected by several factors that are not under the supervision of the DBMS, such as scheduling the operating system or communication delays.

Space utility

The amount of storage space used by the database files and structures the access point.

Transaction throughput

The average number of transactions that can be processed per minute by the system database, and the critical parameters of the transaction system (eg used at booking a place on the plane, banks, etc.). Results of this phase is penentual beginning of the storage structure and access to database files.

Stage 6 Database System Implementation

Once the design is logically and physically complete, we can implement a database system. DDL commands in and SDL (Storage Definition Language) of the DBMS selected, collected and used to create the database schema and database files (which is empty). Now databasetersebut loaded (together) with datanya.Jika data must be changed from the previous computer system, changes in routine may be required to re-format the data that is then inserted into the new database. Transactions database should now be implemented by the programmmer aplikasi.Spesifikasi conceptually tested and linked to the program code with the commands of the embedded DML has been written and tested. One moment of such transactions has been prepared and the data has been entered into the database, the design and implementation phase has been completed, and then the operational phase of the database system begins.

Closing

So in designing the database there are 6 stages. In the design of this database is important to do as well as possible in order to produce a good system.