Presentation is loading. Please wait.

Presentation is loading. Please wait.

1 Databases A database is a collection of related pieces of information A database can be computerised or non- computerised (manual - such as filing system,

Similar presentations


Presentation on theme: "1 Databases A database is a collection of related pieces of information A database can be computerised or non- computerised (manual - such as filing system,"— Presentation transcript:

1 1 Databases A database is a collection of related pieces of information A database can be computerised or non- computerised (manual - such as filing system, phone book etc.)

2 2 Advantages of Computerised Databases speed of information retrieval storage capabilities easy to update and delete ease of access multiple access security

3 3 Disadvantages of Computerised Databases privacy and ethical issues security risks training of staff initial expense (equipment, software) software upgrades

4 4 Terminology A database or a table within a database is made of RECORDS RECORDS contain information about a single item in the database/table. Each record contains FIELDS. A FIELD is a category of data that has been broken down into its simplest form. Firstname, surname, street, suburb

5 5 Terminology In a database or table each ROW represents a record IDCDTitleUnits In StockUnit Price 1Joe Cocker Essentials3$28.00 2The Beatles4$35.00 3Aussie Country Hits2$19.95 IDCDTitleUnits In StockUnit Price 1Joe Cocker Essentials3$28.00 2The Beatles4$35.00 3Aussie Country Hits2$19.95

6 6 IDCDTitleUnits In StockUnit Price 1Joe Cocker Essentials3$28.00 2The Beatles4$35.00 3Aussie Country Hits2$19.95 IDCDTitleUnits In StockUnit Price 1Joe Cocker Essentials3$28.00 2The Beatles4$35.00 3Aussie Country Hits2$19.95Terminology each COLUMN represents a field..

7 7 Terminology Every record in the same table has the same fields. Databases are designed so that each data item is stored only once

8 8 Terminology The method of retrieving information from the database is known as QUERYING the database. A query allows you to display a set of records which meet certain criteria students in year 9 people with postcode 6192 etc.

9 9 Terminology Information taken from a database and designed for hardcopy (printout) is referred to as a REPORT. Reports can be generated from tables or queries. Reports can be formatted in many different styles depending on the target audience.

10 10 Terminology Other database operations include: SEARCHING locate the first record to contain some specific criteria SORTING sorting the database by a nominated field

11 11 Terminology Some database applications also provide a user friendly interface called a FORM. Forms are used to display data from a table or query in an easy to read format.

12 12 Step 1 Determine what data should be stored in each record. Generate a list and eliminate information that is not directly related to the overall purpose of the database.Generate a list and eliminate information that is not directly related to the overall purpose of the database. Planning a Database Careful planning of a database before it is created will prove to be a useful exercise.

13 13 Planning a Database Step 2 What operations are to be performed on the database? Do these operations require any missing information from the list?Do these operations require any missing information from the list? Will there be any need to reduce the list further?Will there be any need to reduce the list further? Adjust the list from step 1

14 14 Planning a Database Step 3 Create a list of fields and field names from step 2Create a list of fields and field names from step 2 Create a description of the data and their types (text, number, YES/NO etc)Create a description of the data and their types (text, number, YES/NO etc) Design a simple form for a single record on paperDesign a simple form for a single record on paper

15 15 Planning a Database Step 4 Create a new database/table using your software with the planned fields.Create a new database/table using your software with the planned fields. Enter the data into databaseEnter the data into database


Download ppt "1 Databases A database is a collection of related pieces of information A database can be computerised or non- computerised (manual - such as filing system,"

Similar presentations


Ads by Google