10 questions on DB2 architecture

 1. Question: What is IBM Db2?

   - Answer: IBM Db2 is a family of data management products, including database servers, developed by IBM. Db2 is a relational database management system (RDBMS) that provides robust features for managing and storing data.

 

2. Question: Explain the difference between Db2 LUW (Linux, Unix, Windows) and Db2 z/OS (Mainframe).

   - Answer: Db2 LUW is designed for distributed systems like Linux, Unix, and Windows, while Db2 z/OS is designed for IBM mainframe systems. The architecture, features, and management of these versions differ to meet the requirements of their respective environments.

 

3. Question: What is a Db2 tablespace?

   - Answer: A Db2 tablespace is a container for storing tables, indexes, and other database objects. It is a logical storage structure that maps to physical storage on disk.

 

4. Question: What is the purpose of the Db2 Catalog and Directory?

   - Answer: The Db2 Catalog contains metadata about the database, such as tables, indexes, and privileges. The Db2 Directory contains information about the physical layout of the database, including tablespaces and storage groups.

 

5. Question: How does Db2 handle transactions, and what is a Db2 commit statement?

   - Answer: Db2 uses a two-phase commit protocol for transactions. The COMMIT statement in Db2 is used to save the changes made during a transaction permanently.

 

6. Question: What is the Db2 Buffer Pool?

   - Answer: The Db2 Buffer Pool is a memory area used to cache data pages and index pages. It helps in reducing the need for frequent disk I/O by keeping frequently accessed data in memory.

 

7. Question: Explain the purpose of the Db2 Lock Manager.

   - Answer: The Db2 Lock Manager is responsible for managing locks to ensure data integrity and consistency in a multi-user environment. It coordinates the locking of resources to prevent conflicts between concurrent transactions.

 

8. Question: What is Db2 SQL PL?

   - Answer: Db2 SQL PL (Procedural Language) is a procedural language extension to SQL. It allows developers to write stored procedures, functions, triggers, and other procedural code within Db2 databases.

 

9. Question: How does Db2 support high availability and disaster recovery?

   - Answer: Db2 supports features like HADR (High Availability Disaster Recovery) to ensure high availability. HADR involves creating a standby database that can take over in case the primary database fails.

 

10. Question: What is the Db2 Explain feature, and how does it help in query optimization?

    - Answer: The Db2 Explain feature is used to analyze the access plan for a SQL statement. It provides information about how Db2 will execute the statement, helping in query performance tuning. Developers can use the EXPLAIN statement to get insights into the execution plan.