Identifying & Correcting Errors in Databases
Identifying Errors

You should always test your database to check that it contains no errors before you start analysing it. This means writing down how you will look through all the data to spot any mistakes. Here are three common test methods:

Test Explanation
Presence Check Checks that all the data has been entered and no field has been left blank.
Type Check Checks that entered values are of a particular type (e.g. that numbers arenít shown as words).
Batch Total Checks that no records have been missed out by comparing the number of questionnaires collected with how many records have actually been entered into the database.

Of course, the only way to check that all the data has been entered accurately is to carefully examine each record and compare them with the original questionnaires collected.

Correcting Errors

  • If it is easy to see what the correct data should be, like when a word is spelt wrong, then you can just change it.
  • If you are unsure what the correct data should be, like when silly data has been entered, then you should delete it. You donít want to cause any problems from people using it when it is wrong.

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