Learning Objectives

Upon successful completion of this chapter, you will certainly be able to:

explain the differences in between information, indevelopment, and also knowledge;define the term database and also identify the procedures to developing one;explain the role of a database administration system;describe the attributes of a file warehouse; anddefine information mining and explain its function in an company.

You are watching: Data exist in the format in which they were collected

Please note, tright here is an updated edition of this book obtainable at https://opentextbook.site. If you are not compelled to use this edition for a course, you may want to examine it out.

Introduction

You have actually already been presented to the first 2 components of indevelopment systems: hardware and also software program. However, those two components by themselves execute not make a computer system beneficial. Imagine if you turned on a computer system, started the word processor, however can not conserve a file. Imagine if you opened a music player yet tbelow was no music to play. Imagine opening a web web browser but tright here were no web pperiods. Without data, hardware and software application are not incredibly useful! File is the third component of an indevelopment system.

Documents, Indevelopment, and Knowledge

File are the raw bits and also pieces of information with no context. If I told you, “15, 23, 14, 85,” you would certainly not have learned anything. But I would certainly have given you data.

Data deserve to be quantitative or qualitative. Quantitative information is numeric, the result of a measurement, count, or some other mathematical calculation. Qualitative information is descriptive. “Ruby Red,” the shade of a 2013 Ford Focus, is an example of qualitative data. A number have the right to be qualitative too: if I tell you my favorite number is 5, that is qualitative data bereason it is descriptive, not the result of a measurement or mathematical calculation.

*
By itself, information is not that useful. To be helpful, it requirements to be offered context. Returning to the instance over, if I told you that “15, 23, 14, and also 85″ are the numbers of students that had registered for upcoming classes, that would be information. By adding the context – that the numbers represent the count of students registering for certain classes – I have actually converted data into information.

Once we have actually put our information right into context, aggregated and analyzed it, we deserve to use it to make decisions for our company. We deserve to say that this intake of information produces knowledge. This understanding deserve to be used to make decisions, collection policies, and also even spark creation.

The last action up the indevelopment ladder is the step from understanding (learning a lot around a topic) to wisdom. We can say that someone has wisdom once they deserve to incorporate their understanding and suffer to produce a deeper expertise of a topic. It frequently takes many kind of years to develop wisdom on a details topic, and also needs patience.

Instances of Data

Ala lot of all software programs need information to perform anypoint useful. For instance, if you are editing a paper in a word processor such as Microsoft Word, the document you are working on is the information. The word-handling software program have the right to manipulate the data: produce a brand-new record, duplicate a document, or modify a paper. Some other examples of data are: an MP3 music file, a video clip file, a spreadsheet, a web web page, and also an e-book. In some instances, such as with an e-book, you might just have actually the capability to check out the data.

Databases

The goal of many type of indevelopment devices is to transform data right into indevelopment in order to generate understanding that have the right to be offered for decision making. In order to perform this, the mechanism should have the ability to take information, put the data right into context, and also carry out devices for aggregation and evaluation. A database is designed for simply such a function.

A database is an organized arsenal of related information. It is an organized repertoire, because in a database, all information is explained and associated through various other data. All indevelopment in a database have to be related as well; sepaprice databases should be created to regulate unrelated information. For example, a database that contains indevelopment around students should not likewise hold information around company stock prices. Databases are not always digital – a filing cabinet, for instance, could be considered a kind of database. For the purposes of this message, we will only consider digital databases.

Relational Databases

Databases can be arranged in many kind of different ways, and thus take many kind of forms. The most renowned create of database today is the relational database. Popular examples of relational databases are Microsoft Access, MySQL, and also Oracle. A relational database is one in which information is organized into one or more tables. Each table has a set of fields, which specify the nature of the information stored in the table. A record is one circumstances of a collection of fields in a table. To visualize this, think of the documents as the rows of the table and also the areas as the columns of the table. In the instance below, we have a table of student indevelopment, with each row representing a student and also each column representing one item of information around the student.

*
Rows and columns in a table

In a relational database, all the tables are associated by one or more areas, so that it is possible to attach all the tables in the database with the field(s) they have actually in common. For each table, one of the areas is determined as a major essential. This key is the distinct identifier for each document in the table. To help you understand also these terms better, let’s walk through the procedure of designing a database.

Designing a Database

Suppose a university desires to develop an information system to track participation in student clubs. After interviewing several people, the design team learns that the goal of implementing the device is to provide much better insight into exactly how the university funds clubs. This will certainly be completed by tracking how many kind of members each club has actually and also exactly how energetic the clubs are. From this, the team decides that the device have to keep track of the clubs, their members, and their events. Using this information, the style team determines that the complying with tables should be created:

Clubs: this will certainly track the club name, the club president, and a short summary of the club.Students: student name, e-mail, and year of birth.Memberships: this table will certainly correlate students with clubs, permitting us to have actually any type of offered student join multiple clubs.Events: this table will certainly track as soon as the clubs accomplish and how many students showed up.

See more: The Handsomest Drowned Man In The World Sparknotes, The Handsomest Drowned Man In The World Summary

Now that the style team has figured out which tables to develop, they should define the certain information that each table will certainly hold. This calls for identifying the fields that will certainly be in each table. For instance, Club Name would certainly be one of the fields in the Clubs table. First Name and Last Name would be areas in the Students table. Finally, since this will be a relational database, eincredibly table have to have a area in widespread via at least one various other table (in various other words: they must have actually a relationship via each other).

In order to correctly produce this partnership, a main key should be schosen for each table. This vital is a unique identifier for each record in the table. For example, in the Students table, it might be feasible to use students’ last name as a method to uniquely determine them. However before, it is even more than likely that some students will share a last name (favor Rodriguez, Smith, or Lee), so a various area should be schosen. A student’s e-mail deal with can be a great choice for a primary crucial, considering that e-mail addresses are distinct. However before, a major crucial cannot change, so this would intend that if students adjusted their e-mail deal with we would have to rerelocate them from the database and then re-insert them – not an attrenergetic proplace. Our solution is to create a value for each student — a user ID — that will certainly act as a main key. We will certainly additionally carry out this for each of the student clubs. This solution is rather common and is the factor you have so many type of user IDs!