What Is Meant by the Closure of a Set of Functional Dependencies? A functional dependency is a one-way dependency between two attributes at any given time. For a unique attribute of value A there is one value of the attribute B associated with it through the relation. Even if the values for the attribute change, there …

The Reasons For Having Variable-Length Records And The Use Of Separator Characters There may be many reasons for a file having variable-length records, as described by Elmasri & Navathe (2015). They are described as one field that may need to be a varying size, a field that may contain a repeating group or value, a …

Different Parameter Types in Database Cost Functions and Their Information Storage The cost function is part of the query cost optimization module of the database management system. Elmasri & Navathe (2015) indicate that the optimizer heuristic rules or query transformations are not the only dependencies used for cost …