Desain Database & ERD: ENTITY RELATIONSHIP DIAGRAM

Desain Database & ERD: ENTITY RELATIONSHIP DIAGRAM:           Sekarang penulis akan membahas mengenai ERD  (Entity Relational Diagram)  nih, teman2. Jadi pada chapter ini, penulis tidak hanya ...

ENTITY RELATIONSHIP DIAGRAM

          Sekarang penulis akan membahas mengenai ERD (Entity Relational Diagram) nih, teman2. Jadi pada chapter ini, penulis tidak hanya akan membahas mengenai seluk-beluk dari ERD, namun juga akan  menjelaskan bagaimana cara membuat ERD dalam database.

Jadi penulis akan membahas mengenai :

1. Entity Relationship Diagram

2. Entity Relationship Model

         Sebelum kita membuat ERD ada baiknya kita berkenalan dulu lah dengan segala sesuatu yang berhubungan dengan ERD.

Ok, lets get started to watch and learn about ERD!!!

Entity Relationship Diagram (as known as ERD) ialah pemodelan data utama dan akan membantu mengorganisasikan data dalam suatu proyek ke dalam entitas-entitas dan menentukan hubungan antar entitas beserta attribut-attributnya.

Berikut penjelasannya, gan :

Entitas (Entity)

Suatu yang nyata dimana kita akan menyimpan data. Jadi contohnya ialah seperti misalnya ERD mengenai Rumah Sakit, nah Entitas nya yaitu entitas penjaga, entitas perawat, entitas dokter dll.

Ada 2 tipe Entitas :

1. Entitas Kuat, merupakan entitas yang tidak memiliki ketergantungan dengan entitas lain.

2. Entitas Lemah, merupakan entitas yang kemunculannya tergantung pada keberandaan entitas lain pada suatu relasi.

Attribut (Attribute)

Suatu tempat atau objek yang berguna untuk menyimpan data-data.

Contohnya kalau dari ERD Rumah Sakit itu seperti misal Entitas nya ialah entitas Dokter, nah attribut nya dapat berupa NoID_Dokter, Nama_Dokter, Spesialis_Dokter, dll.

Jenis-jenis atribut :

1. Atribut komposit = Atribut yang tidak bisa dipecah lagi menjadi atribut yang lebih kecil

2. Atribut atomic = Atribut yang terdiri atas satu komponen tunggal dan tidak bisa diuraikan lg

3. Single-valued attribute = Atribut yang hanya punya satu nilai untuk suatu entitas.

4. Multi-valued attribute = Atribut yang dapat teridir dari sekumpulan nilai untuk entitas.

5. Atribut Derivatif = Atribut yang dihasilkan dari atribut lain yang tidak berasal dari 1 entitas.

Relasi (Relationship)

Hubungan yang terjadi antara satu atau lebih entitas, jadi istilahnya itu hubungan anatar entitas.

Misalnya ni ya, ambil contoh dari ERD Rumah Sakit, kita ambil Entitas Dokter dengan Entitas Pasien. Nah, entitas dokter itu memiliki relasi dengan entitas pasien sebagai "Merawat/Memeriksa/Menyembuhkan", yang artinya Dokter memeriksa/menyembuhkan Pasien, atau Pasien diperiksa/disembuhkan oleh Dokter. Jadi di dalam relasi, harus ada hubungan yang pasti pada antar entitas yang berelasi. Begitu, kawan, mudah bukan?

Derajat relasi atau kardinalitas :

1. One to One (Satu ke satu) = Setiap anggota entitas E1 hanya boleh berhubungan dengan 1 anggota entitas E2, begitu pula sebaliknya.

2. One to Many (Satu ke Banyak) = Setiap anggota entitas E1 boleh berhubungan lebih dari satu dari anggota entitas E2, begitu pula sebaliknya.

3. Many to Many (Banyak ke Banyak) = Setiap entitas E1 boleh berhubungan dengan banyak anggota entitas E1, demikian juga sebaliknya.

Berikut simbol-simbol yang dapat dipakai dalam pembuatan ERD beserta keterangannya :

Guys, dalam membuat suatu ERD, ada 10 langkah yang harus kita lewati. Berikut langkah-langkah dalam pembuatan ERD, beserta penjelasannya, check it out:

Studi kasus:

Skema Kerja Hotel

Spesifikasi database :

• Attribut dari PEGAWAI : Nama,NIP,Jabatan,Telpon,Alamat,Tahun_Masuk.
• Attribut dari TAMU : Nama, Id_Tamu, Alamat, Telpon, Lama_inap
• Attribut dari KAMAR : No_Kamar, Id_kamar
• Attribut dari FASILITAS : Id_tipekamar, Jumlah_kamar, Jenis_tipekamar, Other_fasilitas
• Attribut dari HARGA : Id_harga, Weekdays, Weekend
• Attribut dari TRANSAKSI_MASUK : Id_Transaksi, Reservasi, Tgl_Checkin
• Attribut dari TRANSAKSI_KELUAR: Id_Transaksikeluar,Tgl_Checkout

Step by step pembuatan Enrity Relationship Diagram Skema Kerja Hotel

Menentukan attribut dari setiap entity :

Menentukan Primary Key dari setiap entity :

Menentukan Relationship antar entity :

Menentukan Cardinality Rasio :

Hasil dari ER Diagram :

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5 Things Online Business Considerations

1. Treat your online business like besar.Anda should make thorough work plan. such as planning time and planning about what you are going to do.


2. DisiplinAnda must have the discipline to follow the plan that you have created. No one is going to set you like working for someone else, so you alone must regulate EXPRESS yourself.

3.FokusAnda should focus on running the business. Complete the first one program / ​​planning before doing another program. If you like the frog who likes to jump here jump there, then you will find it hard to be successful in online business.


4.Komitmen and SabarTidak no legitimate business that can make you rich overnight or within days. Do not despair if after running your business during berbukan-month but has not obtained satisfactory results. Keep trying and always improve your skills. If you are patient and committed, you will enjoy your success.

5. Clean and honest in berusaha.Ini very important. If you want your business running and successful for a long time, you have to maintain your reputation with the way business is honest and clean. Once you do "evil", then people will not trust you anymore, and it will destroy your business. Internet business is a business that requires the trust of your prospects anda.Silahkan try running the instructions above, and you will enjoy the results.

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How to / Tips for Music MP3 / CD on your PC or Laptop Computers - Computer General Knowledge Base For New Users / Beginners

Listening to music on both computers in a laptop PC or notebook is something that is mandatory for most people in the world. Maybe for the first time you learn a computer or who have never dabbled can try these easy steps in this article are to be play songs on your computer.

Here are some requirements you must meet before it can run the music on your computer:

A. Tools / Hardware

There must be a minimum of speakers or headphones are lodged in your computer's sound card. Usually the windows and linux computer is equipped with a soundcard that integrates with the mainboard / motherboard.

2. The program Tools / Software

In the windows or linux you have to install a program or software to play songs. Usually in these two types of both windows and linux os existing software to stay where you are looking for just the right time. Or you can also install or install it yourself with your favorite programs such as winamp, kjofol, real one player, and so forth.

Do not forget to run the driver for your sound card. If you can, or ever heard the sound of your computer speakers or earphones sound means the driver has been installed properly. If not then you have to work extra hard to find sound driver on the internet or in store cd and then install it on your computer or laptop pc notebook you.

3. File Video

To be able to hear songs from your favorite artist then you should have a song file from the artist. You can get it from an audio CD or other formats such as mp3, real media, midi and so forth. You must take is buy your songs from artists such good original shape of the original cassette or cd before buying a pirated, because if everyone is buying pirated products then the artist will not get the money and eventually go bankrupt do not want to create a new song or album again .

X. Running a song in your Kompiuter

If everything has been installed then you have to do is insert the cd, flash, external drive, dvd, cda, floppy disks, etc. into your computer and double click the song file you want to listen. Later the program will pop up music player itself and music was playing. Or you can copy the file first songs before running for the next time you no longer need to insert a media file songs before enjoying the songs on your computer. Pretty easy right?

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Ways and Tips Mangaktifkan / Turning On and Off / USB flash disk Repeal Right

Usb flash disk is one of the computer part that is currently booming and rising prestige around the world. Its small and easy to carry anywhere is a suitable tool for the exchange or move-menindahkan file from one place to another with ease. Large storage capacity and prices that were increasingly affordable to the pockets of most people in Indonesia to figure this one product sales increased from time to time.

Behind its simplicity it usb flash drive contains a weakness that we need to know. Usb flash is a product that is sensitive and easily damaged if we are not careful and do not know how to correct operation.

To turn on / turn on the usb flash disk we just flashy flash disk into a usb port on the back, front, or on a cable connection and hub on our computers. If you do not find a suitable port or plug the usb flash disk, then most probably you must add a usb port by buying or borrowing from others. Having successfully entered the usb flash operating system will automatically detect and add a flash drive into the computer. If you are still using windows 98 then you have to install the usb driver ports on your computer. You can get it by searching your driver installation cd which is usually given in conjunction with a flash disk that we receive, or download it from the site of flash products we buy. If you are using Windows 95 to the bottom, then you should re-install your windows to a newer windows.

Flash disk is required to revoke a special way and caution, because if you unplug the usb flash disk when performing a data transfer can be fatal damage to husband's dance on usb flash so it can not be used or improved. Too difficult to fix, because not many experts and many will recommend you to buy a new one.

If we have finished using the usb flash disk then we should not just pull out, but first we turn off the function. The first you have to do is find the icon that when we point with the mouse will appear the words "Safely Remove Hardware" located at the bottom right corner of your screen (windows), right click on the icon kamudian and select "Safely Remove Hardware" on sticking or popping choices. Then, after that select the stop and was followed by selecting ok. Wait a while until a list of hardware to be empty and the resulting signs stating that the hardware (usb flash disk) has been safely be removed, because the hardware is turned off or disabled. Then select the close and the last is unplug your usb flash disk, and have kept in a safe place.

 

Hopefully durable flash disk and if there is damage before the warranty runs out immediately contact the store where you bought the flash for a warranty claim. Usually if the warranty has not run out, the flash disk will be replaced with new ones. Good luck.

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List of Operators and Wireless Fixed Wireless Phones in Indonesia - GSM and CDMA Technology

National Cellular Phone:

A. PT Telkomsel

GSM sympathy - Pre-paid
Aces - GSM - Pre-paid
Hello Card - GSM - Postpaid

2. PT Indosat
Sun - GSM - Pre-paid
IM3 Smart - GSM - Pre-paid
IM3 Bright - GSM - Postpaid
Matrix - GSM - Postpaid

3. PT Excelcomindo
XL Free - GSM - Pre-paid
Thumb XL - GSM - Pre-paid
Xplore - GSM - Postpaid

4. PT Mobile 8 -
Fren Prepaid - Postpaid CDMA
Fren Postpaid - CDMA - Postpaid
Fixed Wireless Telephone (Fixed Wireless Access) National Local Roaming:



A. PT Telkom
Flexi Trendy - CDMA - Pre-paid
Flexy Classy - CDMA - Postpaid

2. PT Indosat
Star One Prepaid - CDMA - Pre-paid
Star One Postpaid - CDMA - Postpaid

3. PT Bakrie Telecom
Prepaid Esia - CDMA - Pre-paid
Esia Postpaid - CDMA - Postpaid 

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