Data Handling

Data Handling

1. Validation Methods

   • Presence Check - Checks that data has been entered into a field and that it has not been left blank.
   • Data Type Check Checks that a value entered is of a particular data type; for example: ensures that a product price is in currency data type.
   • Length Check - Checks than an entered value such as mobile phone is no longer than a particular number of characters
   • Check Digits - These are normally digits on a ISBN Book code that are used as part of a calculation to ensure that the code entered is a valid code.
   • Range Check Checks that an entered value falls within a particular range.
   • Format Check - Checks that an entered value has a particular format

2. Database Info

   • Databases store data in an organised format, this can be electronic or paper based
     • Examples: yel.com, yellow pages
     • Data is organised into records and fields
     • Large amounts of data stored (usually)
     • Easy and Efficient to manage

3. Verification Methods

   • Hash Totals
   • Batch Totals
   • Double Entry of data
   • Visual Check

4. Relationships

   • One-to-one relationship
   • Many-to-many relationship

Imágenes y archivos del mapa