CS348 : A4 (1).pdf
Document Summary
For the scenario described herein, write sql ddl statements (create table etc. ) to create the data model and constraints that best capture the situation. Let r be a relational schema with attributes {v, w, x, y, z} and let f be the set of functional dependencies f = {v wx, xy z, w y, z v }. Now suppose that we have the following decomposition of r: If it is not serializable, then explain why not. Consider the following sequence of requests received by a database system that uses strict two- phase locking: Consider a relation mark with schema (student, course, term. Assume that the instance of mark has 40,000 tuples covering 1000 students, 50 courses, and 10 terms, and that 20 records fit on each page (i. e. , each disk access to the relation retrieves 20 records). Furthermore, assume that the data is clustered by student.