02 Databases

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Databases

What is a database?

 A database is used to store data. The word DATA is actually Latin for FACTS. A database is, therefore, a place, or thing which stores facts.

 An official definition of a database is “a collection

of data related to a particular topic or purpose that

has been organised to allow easy access”. This means a database is used for storing, managing and retrieving information. A database has forms, for you to enter data and reports for printing data in a stylish format.

What is a database?

 Examples of databases are:  Employee records      Telephone directory Mailing list Library catalogue Inventory lists Student database

What is a database?

 Before databases became computerised they were stored in many different ways, such as:  Filing cabinets    Card files Swing files Suspension folders

What is a database?

 Most people’s experience with a database is performing data entry tasks, or running standard reports. The designing of the database is usually left to a member of staff who has particular expertise in this area.

What is a database?

 A computerised database management system:  Is a computer software package   Is an automated version of a manual database system Provides a set of powerful tools for storing, retrieving, editing, sorting, presenting and manipulating data easily and quickly as required.

What is a database?

 A database allows the user to:  Create a database    Add, edit and remove data from the database View and ask questions of the database (eg. Which students are over 16 yrs of age) Create reports in required formats

What is a database?

 Databases are common in most organizations, including government departments, colleges, universities, schools, private companies, clubs, and small businesses.

What is a database?

 They are also used for:      Maintenance of records (eg. Personnel details of all employees) Stock maintenance (eg. Lists of equipment in a factory) Cataloguing items (eg. laboratory equipment or library books) Preparation of mailing lists from a database for names and addresses Maintenance of research by scientists  Summarising information (eg, how many books are out on loan)

What is a database?

 In our Rosny College environment, what types of things would we have in our database about you?

 __________       __________ __________ __________ __________ __________ __________

Advantages of a DBMS

 Most offices keep a filing system to store information such as customer details, product or stock details, employee and supplier details. In a manual filing system, cards and paper forms need to be created, sorted, filed, found, handled, modified and stored. This is tedious and time-consuming, especially when searching for specific information. DBMS: DataBase Management System

Advantages of a DBMS

 Provided the data is stored correctly in a well designed database the user will be able to prepare reports efficiently. Updating new data and deleting old information is simplified. Filing cabinets, paper, folders, etc can all be replaced by one computer and the correct software

Database Terms

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Data

All the information in a data table is data. You can use letters or numbers, or a combination of both.

Database Terms

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Table

A table is a collection of data organised into columns and rows. A single database may contain several tables. These are the first objects that you will create and are essential to using MSAccess

Database Terms

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Field

Each column in the database is a separate field. Information f the same type is stored here and each field has a field name to identify the contents.

Database Terms

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Primary Key Field

MSAccess requires this field to uniquely identify each record in a table. This means the information in the primary key field will identify one record only – such as an invoice, customer or student number. No two invoices, customers or students can have the same number.

Database Terms

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Record

Each row in a data table is a set of fields. This set makes a record.

Database Terms

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Query

A query allows you to ask questions of the database. You can sort the records, search for specific records and calculate numeric fields in a table. For example, in a car yard’s database you might ask for all the Ford cars that are white

Database Terms

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Form

If you enter data directly into a table which you will be doing you can see many records at once. A form provides a simpler view of your data during the data entry process. Only one record is on the screen at a time. It also allows the database designer to prevent mistakes being made.

Database Terms

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Report

A report allows you to print information in your table. They can be printed in a format which is easy to understand.

Database Written Task

Answer the following questions in a Word document.

  What is a database?

What are databases used for?

   Give three example databases that you come into contact with in your life, and explain what type of information they store: When developing databases, why must security be a major consideration?

Is it important to consider confidentiality in determining who can access some databases? Discuss your answer.

Database Practical Task

 Download the Shonky Cars task sheet from the Intranet and work through each of the tasks.

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