![]() This is referred to as an ‘amendment anomaly’. The secretary could also introduce some data inconsistencies if he or she changed the name in one of A Haddock’s records to A Hadock (with one ‘d’). If ‘A Fish’ got married and changed her name to ‘A Haddock’, then the secretary would have to make four changes to the database rather than just one.This results in some of your data being inconsistent. In addition, if you enter the same data over and over again in different places in the flat file, you are more likely to make a mistake when entering in one of the entries. Data redundancy also contributes to larger files, which means longer search times. This is known as ‘data redundancy’ and is a waste of (hard disk) space. Lots of details are held over and over again, for example, the origins and life expectancy of poodles, and the details about the member known as ‘A fish’.Because dogs do not have their own ID number, you cannot enter in a ‘new’ breed until a member owns a dog of that breed.Their personal details just happen to be the same! You cannot tell them apart from the details held in the flat file. There are different two dogs, both called ‘Gov’. It is therefore impossible to find an individual dog. Dogs do not have their own unique identity number. ![]() This means that you cannot pick out one and only one record if you searched for a member by their membership number. The problem is that some records (some rows) have the same ID number. This should be unique for each member and is known as the Primary Key. ![]() You can see that in the flat file, every member has an ID number.They provide many of the sorting and searching tools commonly needed by users of the database.Flat files are relatively quick and easy to set up and use. ![]()
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