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Creating A Database. Mr Conti Year 10 – Computing Lesson 5. Learning Objectives. By the end of this lesson we will have learned: How databases help us to organise data. How different fields help us to understand and arrange data. How we can validate and verify data to avoid making errors.
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Creating A Database Mr Conti Year 10 – Computing Lesson 5
Learning Objectives By the end of this lesson we will have learned: • How databases help us to organise data. • How different fields help us to understand and arrange data. • How we can validate and verify data to avoid making errors.
What is a Database? • Think – Think about the answer to the question • Pair – Discuss it with you neighbour • Share – Share your answer with the class
What is a Database? Datais unprocessed information. This information can take many different forms. 30,000 Beck male Mr Adam single 6 Western Road However, without a structure for the data to be kept in, it is meaningless. A- 01864 830002 Title: Forename: Surname: Gender: Address: Blood type: Marital status: Telephone: Mr Adam Beck male 6 Western Road A- single 01864 830002 A database gives structure to the data so that it can be processedtogive us information. Databases can be sorted and searched to help us find relevant and useful information.
For the record Before computers were invented, organizations kept information on record cards in card boxes, or on sheets of paper in files and filing cabinets. J. Vincent Address: 6 Broad Lane, Winsford Telephone: 0987 654675 Date of Birth: 02.05.1980 Filing cabinet Files Record
Much more convenient Now, databases are created and stored on a computer. Computer File Record
Inside the fields Each record is made up of fields – categories of information. The fields that are listed in this database are: • Name • Telephone • Surname • Date of Birth • Address
Task Time • Pupil Resources • ICT • Mr Conti • Year 10 • L5 • Task 1 • 10 Minutes
Let’s get it right We need to specify a data typefor each field. • Name, Surname and Address are textfields. • Telephone number is a textfield rather than a number field, so that the 0 at the start is not ignored. • Date of Birth is a datefield. Other data types can include currency, time and fractions.
Task Time • Pupil Resources • ICT • Mr Conti • Year 10 • L5 • Task 2 • 15 Minutes
Reducing mistakes Using data typeshelps to ensure that the data entered in the record is valid. • If you try to type text in a date/time data field, the program will not allow it. • However, it will let you put numbers in a text field. • Mistakes are reduced by making sure the data is valid. • Validation does not stop you typing in the wrong date. For that you need to check against the original document. This is called verification.
Checking for errors Most database programs allow users to create their own validation checks, by setting the rules or limits for certain fields, such as: • charactertype (number or letter or both) • length of field (how many characters, for example a title between 2 and 4 characters) • range (specify from and to, for example an exam mark from 0 to 100). If the data that is entered is not valid, an error message will appear on the screen to inform you.
Plenary • I understand how databases help to organize data. • I understand how different fields help us to understand and arrange data. • I know how to validate and verify data to avoid making errors.