Question: 1 Which of the following statements is true about Db2 for z/OS data sharing? A. Data sharing allows multiple Db2 subsystems to share a single database. B. Data sharing enhances data security by encrypting all database communication. C. Data sharing improves query performance by utilizing distributed processing. D. Data sharing enables the replication of data across multiple Db2 databases. Answer: A Explanation: Data sharing in Db2 for z/OS enables multiple Db2 subsystems to share a single database. It allows for parallel execution of transactions across the subsystems, ensuring high availability, scalability, and workload balancing. Each subsystem maintains its own buffer pools and lock structures but shares the same database objects, providing a shared and consistent view of the data across the subsystems. Question: 2 Which of the following indexing techniques is most suitable for improving query performance in situations where the data is frequently updated? A. Clustered index B. Non-clustered index C. Bitmap index D. Partitioned index Answer: B Explanation: A non-clustered index is more suitable for situations where the data is frequently updated. Unlike a clustered index, which physically orders the data on disk based on the index key, a non-clustered index creates a separate structure that references the data. This separation allows for better performance during data modifications, as updates do not require reordering of the entire data set. Question: 3 Which of the following authentication methods provides the highest level of security in IBM Db2 for z/OS? A. User ID and password authentication B. Lightweight Directory Access Protocol (LDAP) authentication C. Kerberos authentication D. Certificate-based authentication Answer: D Explanation: Certificate-based authentication involves the use of digital certificates to verify the identity of users. It provides a higher level of security compared to user ID and password authentication, LDAP authentication, or Kerberos authentication. With certificate-based authentication, users must possess a valid certificate, which is issued by a trusted certificate authority, to access the Db2 database. Question: 4 During the installation of IBM Db2 for z/OS, which component is responsible for creating and managing the database catalog? A. Db2 installation panel B. Db2 Data Sharing Group (DSG) C. Db2 Catalog System (DCS) D. Db2 Initialization Parameters (DIP) Answer: C Explanation: The Db2 Catalog System (DCS) is responsible for creating and managing the database catalog during the installation of Db2 for z/OS. The catalog contains metadata about the database objects, such as tables, indexes, and views. It is a crucial component for the functioning of Db2 and is used by the system to locate and access the database objects. Question: 5 What is the purpose of a recovery log in IBM Db2 for z/OS? A. It keeps track of all database modifications for auditing purposes. B. It provides a backup of the entire database for disaster recovery. C. It records all changes made to the database for transaction recovery. D. It stores historical data for analytical reporting. Answer: C Explanation: The recovery log, also known as the transaction log, is a crucial component of database recovery in Db2. It maintains a record of all modifications made to the database, such as inserts, updates, and deletes. In the event of a system failure, the recovery log is used to restore the database to a consistent state by applying the logged changes to the database. Question: 6 Which Db2 feature enables the integration of a distributed DBMS with IBM Db2 for z/OS? A. Data Propagation B. Distributed Relational Database Architecture (DRDA) C. Data Sharing D. Db2 Connect Answer: B Explanation: DRDA is a network architecture that enables the integration of a distributed DBMS with IBM Db2 for z/OS. It provides a standardized protocol for communication and data exchange between different database systems. DRDA allows applications on distributed systems to access and manipulate data in Db2 for z/OS seamlessly, facilitating distributed access and data sharing. Question: 7 Which of the following statements is true about database normalization? A. It reduces data redundancy and improves data integrity. B. It improves query performance and reduces disk space usage. C. It simplifies data access and improves data availability. D. It increases data concurrency and reduces data locking. Answer: A Explanation: Database normalization is a process that organizes data in a database to eliminate redundancy and improve data integrity. By breaking down data into smaller, logical units, normalization reduces data duplication, enhances data consistency, and minimizes the risk of data anomalies. Question: 8 In IBM Db2 for z/OS, which utility is used to load large amounts of data efficiently into a table? A. LOAD utility B. IMPORT utility C. REORG utility D. COPY utility Answer: A Explanation: The LOAD utility in Db2 for z/OS is specifically designed to load large amounts of data efficiently into a table. It provides high-speed data loading capabilities and supports various input formats, such as delimited files, sequential files, and binary files. The LOAD utility is optimized for bulk data loading and is often used during initial data population or when a significant amount of data needs to be loaded. Question: 9 Which of the following statements accurately describes the purpose of a materialized query table (MQT) in IBM Db2 for z/OS? A. It provides a temporary storage area for intermediate query results. B. It allows for the distribution of data across multiple database partitions. C. It caches frequently accessed query results to improve query performance. D. It enables real-time replication of data between Db2 databases. Answer: C Explanation: A materialized query table (MQT) in Db2 is used to cache frequently accessed query results. By storing the query results in a physical table, Db2 can avoid executing the query repeatedly, thus improving query performance. The data in an MQT is refreshed periodically based on defined refresh criteria, ensuring that the cached results remain up to date.