Which utility is commonly used for database backup and recovery tasks in DB2?

  • db2backup
  • db2dart
  • db2recovery
  • db2restore
db2restore is commonly used for database backup and recovery tasks in DB2. It allows users to restore the database to a previous state by applying archived log files or backup images. db2backup is used to create full or incremental backups of the database, while db2recovery is used to roll forward or roll back changes to the database. db2dart is a diagnostic tool used to analyze and repair corrupted database objects. 

Row-level locking in DB2 provides ________ granularity for locking compared to table-level locking.

  • Coarser
  • Finer
  • No locking
  • Similar
Row-level locking in DB2 provides finer granularity for locking compared to table-level locking. With row-level locking, only the specific rows that are being modified are locked, allowing other transactions to access and modify different rows concurrently. This reduces contention and improves concurrency in the database. 

Which DB2 feature facilitates automatic failover in the event of a primary server failure?

  • Data Partitioning
  • Database Encryption
  • HADR (High Availability Disaster Recovery)
  • Multi-Instance Failover
HADR (High Availability Disaster Recovery) in DB2 facilitates automatic failover by maintaining a standby server that automatically takes over in the event of a primary server failure. 

What is the behavior of the STDDEV() function in DB2 when applied to a column with NULL values?

  • It returns NULL
  • It returns 0
  • It returns 1
  • It returns error
The correct option is 1. The STDDEV() function in DB2 returns NULL when applied to a column with NULL values. It does not include NULL values in the calculation of standard deviation. 

Scenario: A DBA is optimizing database performance in DB2 and considers using user-defined functions. How can UDFs contribute to performance tuning efforts?

  • User-defined functions can execute complex operations directly within SQL queries, reducing the need for multiple queries.
  • User-defined functions can execute only simple calculations, limiting their impact on performance tuning efforts.
  • User-defined functions can leverage DB2's query optimizer, leading to efficient execution plans.
  • User-defined functions can only be called from application code, bypassing the query optimization process.
User-defined functions in DB2 can contribute significantly to performance tuning efforts by leveraging the query optimizer. When properly designed and utilized, UDFs can enable the optimizer to generate efficient execution plans, leading to improved query performance. This allows DBAs to streamline database operations and enhance overall system performance. 

DB2 handles invalid XML characters within tags by ________ them with equivalent HTML entities.

  • Encoding
  • Escaping
  • Ignoring
  • Replacing
DB2 handles invalid XML characters within tags by escaping them with equivalent HTML entities. This ensures that the XML remains well-formed and can be processed correctly by XML parsers. Escaping involves replacing characters like '<' and '>' with their corresponding HTML entities such as '<' and '>'. 

During DB2 installation, the installation directory is typically referred to as ________.

  • DB2_HOME
  • DB2_DIR
  • DB2_ROOT
  • DB2_INSTALL_PATH
The correct answer is option C. The installation directory in DB2 is commonly known as the DB2_ROOT directory. This directory contains all the files and subdirectories required for the DB2 installation process. 

Scenario: A DBA needs to generate XML output from a query result in DB2 but wants to customize the format according to specific requirements. Which feature of DB2 can help achieve this?

  • Exporting query results to an external XML file and then modifying the format.
  • Using the TOXML function to directly convert query results into XML format.
  • Utilizing DB2's built-in XML templates for customizing XML output.
  • XMLTABLE allows for generating XML output from query results and offers customization.
XMLTABLE is a powerful feature in DB2 that allows a DBA to generate XML output from query results while providing flexibility in customizing the format according to specific requirements. With XMLTABLE, the DBA can define the structure of the XML output, including elements, attributes, and namespaces, thus achieving the desired format customization directly within the database. This feature streamlines the process of generating customized XML output from DB2 query results. 

In disaster recovery planning, what does the term "RPO" stand for?

  • Recovery Performance Optimization
  • Recovery Point Objective
  • Recovery Point Overhaul
  • Recovery Process Optimization
In disaster recovery planning, "RPO" stands for Recovery Point Objective. RPO refers to the maximum acceptable amount of data loss measured in time before a disaster occurs, which determines the frequency of data backups. 

In Visual Explain, what does a red arrow between nodes typically indicate?

  • Data Movement
  • Error Condition
  • Index Usage
  • Sort Operations
In Visual Explain, a red arrow between nodes typically indicates data movement. This means that data is being transferred between different stages of query processing, such as between tables or between sorting operations. Understanding data movement can help optimize query performance by minimizing unnecessary data transfers. 

Scenario: A software development team is experiencing slow query performance in their DB2 database. How can they leverage normalization and denormalization techniques to optimize database performance?

  • Denormalize specific tables to eliminate joins and reduce query execution time.
  • Normalize the database to reduce redundancy and improve query performance.
  • Optimize SQL queries and use proper indexing techniques to improve query performance.
  • Partition large tables and indexes to enhance parallel processing.
In addressing slow query performance, normalization is essential to minimize redundancy and improve data organization, thus enhancing query performance. However, denormalization can also be beneficial in specific cases, such as eliminating joins to reduce query execution time. Partitioning large tables and indexes can enhance parallel processing and improve query performance. Additionally, optimizing SQL queries and utilizing proper indexing techniques are crucial for optimizing database performance. 

Denormalization is a process of ________ the normalized relational database schema.

  • Combining
  • Optimizing
  • Reversing
  • Splitting
Denormalization involves combining normalized tables to reduce redundancy and improve query performance by eliminating the need for excessive joins. This often leads to faster query execution.