Question

Testing for conflict serializability: Algorithm 21.1: Constructs a _____ (serialization graph) - a graph with directed edges?

1) Dependency graph
2) Precedence graph
3) Conflict graph
4) Serialization graph

Answer 1

Algorithm 21.1 in the context of database systems constructs a precedence graph, also known as a serialization graph or conflict graph, which is used to test for conflict serializability by showing conflicts among concurrent transactions.

Step-by-step explanation:

The algorithm in question is used for testing for conflict serializability in the context of database systems. The correct term to fill in the blank would be precedence graph (also known as a serialization graph or conflict graph). When multiple transactions occur concurrently, a precedence graph is used to represent the conflicts among them based on read and write operations. If the graph has cycles, the schedule is not conflict-serializable. However, if the graph is acyclic, we can conclude that the schedule is conflict-serializable. In short, Algorithm 21.1 constructs a precedence graph.