Computer Knowledge
Database Management Systems
5,344 Questions
Database Management Systems (DBMS) form the core framework for data storage, retrieval, and security in modern software applications. Concepts such as the E-R model, backup planning, SQL integration, and big data architecture are essential for computer knowledge sections. This hub offers a comprehensive set of practice questions to master DBMS fundamentals and advanced database operations.
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Database Management Systems Questions
A
Correct answer
Explanation
Pull mode information delivery relies on users actively requesting reports or queries, such as ad hoc queries, prestored reports, and OLAP analyses, rather than receiving pushed notifications.
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Master data management
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Data Quality Management
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Metadata Management
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Data Security Management
A
Correct answer
Explanation
Master Data Management (MDM) is specifically designed to create and maintain a single, consistent view of an organization's critical data entities (like customers, products, suppliers) across all systems and applications. Data Quality Management focuses on improving data accuracy, Metadata Management manages data about data, and Data Security Management protects data access - none of these specifically create unified reference views.
A
Correct answer
Explanation
ETL (Extract, Transform, Load) is recommended for large data volumes with low quality because transformation happens before loading, allowing early error detection and correction. ELT loads raw data first then transforms it, which is better for cloud environments with good data quality. ELTL is not a standard pattern. EII (Enterprise Information Integration) provides virtual views without physical data movement.
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Consolidation
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Registry
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Coexistence
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Transaction
B
Correct answer
Explanation
Registry style MDM maintains a centralized index or registry of master data without physically consolidating all records. This allows real-time access to reference data across systems. Consolidation physically merges data, Coexistence maintains separate copies with synchronization, and Transaction style supports real-time transactions but doesn't provide centralized reference in the same way.
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Minimizes database queries
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Multiple execution of report
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Increases Network traffic
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Both a and c
A
Correct answer
Explanation
Report bursting generates multiple personalized report segments from a single report execution, which minimizes database queries compared to running reports separately for each user. It does not involve multiple execution of the same report. By delivering only relevant sections to each recipient, it actually reduces network traffic rather than increasing it.
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Staging Area
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Data Mart
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ODS
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None of the above
A
Correct answer
Explanation
The Staging Area is a temporary storage location where data extracted from source systems is held before transformation and loading into the data warehouse. It allows for ETL processes to work without impacting source systems, enables data quality checks, and provides a recovery point. Data Marts are subsets of data warehouses. ODS is for operational reporting.
B
Correct answer
Explanation
ODS (Operational Data Store) is designed to be volatile, meaning data can be updated, deleted, or modified frequently. This volatility is what makes it suitable for operational reporting and tactical decision-making. Data Warehouses, in contrast, are non-volatile (data is not updated or deleted once loaded). The statement claims ODS is non-volatile, which is false.
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Detailed decision making
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Operational reporting
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Drill through analysis
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All of the above
D
Correct answer
Explanation
ODS supports detailed, current operational data that enables detailed decision making at the operational level. It provides operational reporting capabilities for day-to-day business monitoring. Drill-through from data warehouses to ODS is a common pattern for accessing detailed transactional data. Therefore, ODS provides all these capabilities.
B
Correct answer
Explanation
Active data warehouse architecture uses a centralized, integrated approach where data marts are derived from the same warehouse and share dimensions/facts, not kept separate and segregated. The statement actually describes the Independent Data Mart architecture, where each mart operates as an isolated silo. Active warehouses emphasize consistency and integration across business units.
B
Correct answer
Explanation
ELT (Extract, Load, Transform) is recommended for small and medium data volumes with good data quality and off-peak loads because it leverages the target system's processing power after loading. ETL transforms before loading, adding overhead. ELTL and EII are not standard data integration patterns in this context.
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DSPLCK
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DSPOBJLCK
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DSPSYSLCK
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DSPACTLCK
B
Correct answer
Explanation
DSPOBJLCK (Display Object Locks) is the correct IBM i command to show active locks on any object. DSPLCK is not a valid command, DSPSYSLCK would display system-level locks (not object-specific), and DSPACTLCK is not a standard command.
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DB2/IDMS Database is not up
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Any data exception problem SOC7, SOC4 etc
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Runaway Task
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All of the above.
B
Correct answer
Explanation
ASRA is a CICS transaction abend that occurs when a program encounters a data exception or program check, such as SOC7 (data exception) or SOC4 (storage violation). Option A would cause an AEY3 or AEY9 abend, while option C is an ASRA timeout abend (different type). ASRA specifically means the program crashed.
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a database directory
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a database tablespace
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a database bufferpool
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a database column
B
Correct answer
Explanation
In DB2, locks can be obtained at the tablespace level, which is a logical grouping of tables. Locking at the tablespace level provides concurrency control for data managed within that tablespace. Options like directory, bufferpool, and column are not lockable objects in DB2.
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Removes all the statements in source code
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Replaces all the SQL statements into corresponding host language CALL statements
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Replaces SQL statements into corresponding host language statements
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None of the above
B
Correct answer
Explanation
The DB2 precompiler processes embedded SQL statements in host language source code and replaces them with CALL statements to DB2 runtime services. This transformation allows the host language compiler to process the code without needing to understand SQL syntax directly.
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Edited form of the SQL statements with some additional information
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Complied version of SQL statements
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Complied version of source code
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None of the above
A
Correct answer
Explanation
A Database Request Module (DBRM) contains the SQL statements extracted from the source program by the precompiler, along with some additional control information.