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Database Design Anomalies and Solutions

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Added on  2019-09-13

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This article discusses the various database design anomalies such as insertion, deletion, and modification anomalies. It provides examples and solutions to these anomalies. The article also mentions the primary key for each database and the problems that arise due to these anomalies. The subject is Database Management System, and the course code is ISTM 4121. The article is relevant to students studying computer science, information technology, and related fields. The college or university is not mentioned.
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ISTM 4121 – Fall 2016Name:Ans:NAMEGPAMAJORIDADDRESSCOURSE-IDC-DESCGRADECREDITLincolnPlatoPlatoJonesJonesJonesJonesDunnWilliamWilliamWilliamBrownBrown3.63.43.43.03.03.03.03.23.13.13.13.53.5Poly-sciPhiloPhiloEngEngEngEngEngPhysPhysPhysChemChem444412341234789078907890789033331111111111112233223333Main11 1st11 1st22 2nd22 2nd22 2nd22 2nd33 3rd44 4th44 4th44 4th1 Broad1 BroadSA101SA101BA202SA101BA202DP209AC101DP209SA101AC101BA202DP209AC101Sandbox 1Sandbox 1Bskweav 2Sandbox 1Bskweav 2DatabaseAcctngDatabaseSandbox 1AcctngBskweav 2DatabaseAcctngAACDEABBFADCA3323233333233Primary Key:here primary key is a composite key that is: (courseID and ID)Insertion:If want to add new course with new course id and its description then currently according to thisdatabase we are unable to add new course details. We have to add at least one student details to add new course details.Deletion:Suppose the batch of students are done with the course and know we need to delete the record of students from the database but we also want to keep course details because they are still running in university. This type of database design create a problem because we have to delete unwanted data too.There may be one more reason for deletion anomaly and that is supposed we want to keep data for all student but we want to delete that course details from the database that is not supposed to
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run anymore by the university. This also creates a problem where we have to delete unwanted data too.Modification:Suppose the student wants to change his/her address. This requires that all tuples corresponding to that student name of the table are modified by given new address. If we fail to update all the tuples for that student then two different records for that student may store and this leads inconsistent database.
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