Suppose the telephone numbers now have to have a dash between the area code and the rest of the number, like this 0223-44033. Other methods avoid this wasted storage.ĥ. If there are tens of thousands of records, there may be many people having no email address, but each record in a flat file database has to have the same fields, whether they are used or not. Consider a situation where the database now needs to hold an extra field to hold their email address. Again, this is fine - but suppose Sandra Jones now wanted to be known as 'Sandra Thompson' after re-marrying? This will have to be done over potentially many records and so flat file updates are more error-prone than other methodsĤ. Suppose that this flat file database also stored their work place details - this will result in multiple records for each person. This is fine for that purpose, but suppose you only wanted to extract Mrs Jones' record. This is because the person producing this database decided they may want to sort on identical telephone numbers and so has applied identical ID to the two records. Notice that Mr & Mrs Jones have identical ID's. Later you will see how 'primary keys' are used to prevent this.Ģ. This is because there is no mechanism built in to the system to prevent duplication. ![]() As more and more records are added to the database it becomes difficult to avoid duplicate records. Consider the flat file table you saw earlier IDġ. Record can be viewed or extracted on the basis of simple criteriaĮveryday things like business contacts, customer lists and so on can be stored and used in a flat file database.īut they do have some serious disadvantages when it comes to more than a few thousand records.Simple sorting of records can be carried out.Easy to set up using a number of standard office applications.Placing data in a flat file database has the following advantages
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