A column or set of columns is called a Candidate Key when its values can uniquely identify the row in the relation.To move to First Normal Form a relation must contain only atomic values at each row and column.In unnormalized relations data can repeat within a column.First step in normalization is to convert the data into a two-dimensional table.Data Base: Structured Techniques for Design, Performance, and Management. Normalization is a multi-step process beginning with an "unnormalized" relation.Normalization theory is based on the observation that relations with certain properties are more effective in inserting, updating and deleting data than other sets of relations containing the same data.Advantages and failings of DBMS technology.Effectiveness and Efficiency criteria for database designs.We will examine the tables for the Acme Widget Company derived from the ER diagram.Relationships are indicated by common columns (or domains) in tables that are related.A properly normalized ER diagram will indicate where intersection relations for many-to-many mappings are needed.Each entity in the ER Diagram becomes a relation.We will concentrate on Ordering and Inventory.SIMS 202: Information Organization and Retrieval School of Information Management and Systems
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