Suppose that you need to update one value of the column SalesCost in a relation.The way the relation is constructed,this value actually needs to be changed in three different rows.However,you only change the value in two of the rows.You have just created a(n)________.
A)normalization anomaly
B)insertion anomaly
C)update anomaly
D)deletion anomaly

Question

Quizplus · Accepted Answer

An update anomaly occurs when an action such as changing a value in a relation leads to inconsistencies in the database. In this case, updating one value of the column SalesCost in a relation, but only changing the value in two out of three required rows, leads to an inconsistency in the database, thus creating an update anomaly. Option A, normalization anomaly, occurs when a table is not properly normalized. Option B, insertion anomaly, occurs when adding a new record to a table requires the addition of unnecessary data. Option D, deletion anomaly, occurs when deleting data from a table accidentally removes necessary data as well.

Suppose That You Need to Update One Value of the Column