4.3.4: Two Approaches to Database Design Following relational database creation rules in order to design a database free from delete, insert, and update anomalies The loss of all information about an entity when a row is removed from the table A non-null primary key ensures that every row in a table represents something that can be identified Anc is st upd only caus inco Relational Data Model Tuple Primary key Foreign Key Update Anomaly Insert Anomaly Delete Anomaly Relational Database Entity Integrity Rule Referential Integrity Rule Normalization A database built using the relational data model A non-primary key item is stored multiple times; updating the item in only one location causes data inconsistencies One or more database attributes that uniquely identifies each row in a table Two-dimensional table: each row is a unique entity (record) and each column is a field where data are stored A database table row that contains data about a specific item An attribute that is a primary key in another table; used to link the two tables Inability to add records to a database Foreign keys must have values that correspond to the value of a primary key in another table 11