Databases: Data Storage
Once you have obtained the data, you need to store it.
Database programmes are used to store data.
Important terms
Database |
Files |
Records |
Fields |
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 |
 |
 |
A database is a collection of data. To keep the data organised it is sorted into files. Each file contains sets of records. Each record consists of fields. Each field can contain different types of data.
Types of Data
Logical / Boolean |
Alphanumeric / Text |
Numeric |
Date |
|
This data can only be one of two characters. Y for yes N for no |
Data consisting of text and numbers. |
Data which is only numbers. |
Dates are stored as numbers, but it is important to specify that the data is a date. |
The table above shows the most common types of
data. Different software programmes have additional data types, but these are just variations on the above.
When working with databases you must specify what type of data will be found in each field. This allows the computer to validate (check) that the correct data has been entered in each field. Data validation is an important aspect of entering data. We will learn more about this later.
The Key Field
When setting up a database, it is important to identify one field as the key field. The data in this field is unique to the record and is used to identify an individual record.
Below is an example of a database file |
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Database |
Files |
Records |
Fields |
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|
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|
The database is a collection of data about books. |
This specific file shows math books. |
Each row is a record about a specific book. |
Each column consists of fields. |
You will note, each field has been given a name; Title, Edition and so on. Each field contains different types of data.
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Logical / Boolean |
Alphanumeric / Text |
Numeric |
Date |
On Loan |
Title Author Publisher ISBN Number |
Edition / Copyright |
Purchase Date |
The field called “ISBN Number” has been made the key field because ISBN numbers are unique to each book and as such will never occur more than once.
Miscellaneous
ICT Tutorials
- Databases
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