Database theory

PT2520 UNIT 4 Clarence Gross 2/2/13 Normalization is the process of removing anomalies from database design. True Not being able to insert data because other data is required is an example of an insertion anomaly. True An insertion anomaly occurs when you enter data inaccurately. False An update anomaly occurs when you have to update the same data in multiple places. True A deletion anomaly occurs when you are unable to delete data in a primary key table because a foreign key table contains records related to that data. False Normal forms are sets of rules designed to remove anomalies and redundancy from database design. False The First Normal Forms removes all repeating groups and arrays. True

PT 2520 Unit 1 Homework Clarence Gross 12/22/12 At its simplest, a database can be seen as a collection of related data. True A delimited file is a file where the length of the file is limited. False A delimited file is one in which the data is separated by a character such as a comma. True All fixed length files are of the same length. True In relational database, logic design is kept separate from physical design. True A hierarchical database is designed with a tree-like structure that resembles a file system. True Codd defined the core principles of a relational database in 1970 True Data redundancy improves the integrity of a database. False In a diagram, crows feet notation conveys more information about the relationships. True