D1

Deletion of Fields/Records

Deletion of fields/ records is mostly caused by human or error files being corrupted. If you back up your database it allows important data to be restored when deleted. You can have different backup times this means you could set it every 5-10 minutes. Also a backup could be deleted to avoid this you should save your backups in a different site.

Incorrect Data Types

A way to decrease incorrect data types is on Forms input masks are.Another way do decrease incorrect data types is using multiply choice question. This also allows the data to be entered quicker and makes it easier to complete a data form. 

Validation

Validation makes sure that data that the database is putting is accurate and correct. This is easy to do all you can do it in the setting rules in the design stage. Limit checks are used to minimise the amount of characters entered for a password or user name. Range checks allow the database to set a range between one character to another such as date of birth 1-12months. Grammar checks make sure that the data isn’t spelt incorrectly. Data type checks, these ensure that the input data is correct if not a error message pops up. These are some of the types of checks/rules that can be added to a database to ensure correct and valid information.

Null values

Null values are shown when data isn’t entered into a textbox on the form mainly come up with the star symbol (*). This means that the information is extremely important and needs to be filled in if you click accept the error message should pop up and you’d have to go back and fill the unfilled box in.