Computer Knowledge
Database Management Systems
5,543 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
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Collects and presents the disparate data into views that are intelligent and fact based
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Allows for more quality decisions to be made and Moves these to a more dynamic plane
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Brings new insights and perspectives to questions and answers inherent in data
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All of the Above
D
Correct answer
Explanation
Business Intelligence (BI) systems combine all three functions: they aggregate and present data in meaningful ways (A), enable better decision-making through data-driven insights (B), and provide analytical perspectives on business questions (C). BI is a comprehensive approach to transforming raw data into actionable business insights.
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Subject Oriented, Integrated, Volatile and Time invariant collection of data
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Subject Oriented, Integrated, Non-volatile and Time invariant collection of data
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Subject Oriented, Integrated, Non-Volatile and Time variant collection of data
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None
C
Correct answer
Explanation
A data warehouse is characterized by four key properties: subject-oriented (organized by major subject areas), integrated (data from multiple sources unified), non-volatile (once loaded, data doesn't change), and time-variant (data reflects historical changes over time). These distinguish it from operational databases that are volatile and current-focused.
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Powerful and natural extension of the data warehouse
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Extends information to the departmental environment from an enterprise environment
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Interprets and structures data to suit departments’ specific needs
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All of the above
D
Correct answer
Explanation
A data mart is a focused subset of an enterprise data warehouse, tailored to specific departmental needs (C). It extends warehouse capabilities to business units (B) and serves as a natural extension of the overall warehousing architecture (A). Data marts provide optimized, department-specific views while maintaining consistency with enterprise data.
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Online Transactional Processing and Online Analytical Processing systems
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Online Transactional Processing and Organized Analytical Processing systems
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Online Transactional Processing and Online Application Processing Systems
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None
A
Correct answer
Explanation
OLTP (Online Transactional Processing) handles day-to-day operational transactions like orders and updates, while OLAP (Online Analytical Processing) supports complex analytical queries and reporting on historical data. They serve different purposes: OLTP for operational efficiency, OLAP for business intelligence and decision support.
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Typically detailed data only, often resulting in very large data volumes
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Contains summarised and detailed data
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Contains Summarized data only
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None
A
Correct answer
Explanation
An Operational Data Store (ODS) contains detailed, current data drawn directly from operational systems, not summarized aggregates. This detailed granularity enables operational reporting and real-time analysis but results in large data volumes since no aggregation occurs.
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Generally dimensionally modelled and tuned to optimise query performance
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Generally modelled to support rapid data update
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Should not be in Dimensional Modelling way
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None
A
Correct answer
Explanation
Data warehouses use dimensional modeling (star schema, snowflake schema) to optimize query performance for analytical workloads, unlike transactional systems designed for rapid updates. Dimensional modeling organizes data into fact tables (measurements) and dimension tables (descriptive attributes) for efficient multi-dimensional analysis.
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Data about Data
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Machine level Data
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Characteristics of Data
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Relationship between Data
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Tables with Measures that cannot be added across all dimensions
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Tables, also known as lookup or reference tables, contain relatively static/ descriptive data
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Tables, represent data, usually numeric and additive, that can be analyzed and examined
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None
B
Correct answer
Explanation
Dimension tables contain descriptive, contextual attributes that provide meaning to numerical measurements in fact tables. These include relatively static reference data like product names, customer demographics, geographic information, or time periods. Dimensions serve as the 'who, what, where, when' for analytical queries.
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Tables typically contain facts and primary keys to the dimension tables
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Tables typically contain facts and foreign keys to the dimension tables
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Tables containing detail level facts or facts that have been aggregated
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None
B
Correct answer
Explanation
Fact tables store quantitative measurements or metrics (facts) along with foreign key references to dimension tables. These foreign keys connect each measurement record to its dimensional context (e.g., which product, which customer, which time period). Facts are typically numeric and additive across dimensions.
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Star Schema is a relational database schema for representing multidimensional data that contain one or more dimensions and fact tables
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A snowflake schema is a term that describes a star schema structure normalized through the use of outrigger tables
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Snow flaking NOT recommended in most cases because of the very big dimension table’s size
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Star schema is not recommended as it will be in highly normalized state
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Attribute
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Fact
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Hierarchy
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Filter
A,B,C
Correct answer
Explanation
In dimensional modeling schemas, core schema objects include Attributes (descriptive properties), Facts (measurable metrics), and Hierarchies (organized level structures). These elements form the foundation of dimensional models used in data warehousing and OLAP systems. Filters are query-time mechanisms, not schema definition objects.
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Report Filter
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View Filter
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both 1&2
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none
A
Correct answer
Explanation
In MicroStrategy, Report Filters apply conditions directly at the data warehouse level by modifying the SQL WHERE clause sent to the database. View Filters are applied after data retrieval, filtering the result set already returned from the warehouse. This distinction is crucial for query performance optimization.
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Set of filters
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Attribute elements
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both 1&2
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none
B
Correct answer
Explanation
Consolidations in MicroStrategy are custom groupings created by combining specific attribute elements into logical sets. For example, you can create a consolidation called 'West Coast' by grouping specific state attribute elements like 'CA', 'OR', 'WA'. They are not created from filters, which are conditions rather than element groupings.
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Source Systems
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Data Warehouse
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ETL process
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Metadata
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Microstrategy applications
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All of the above
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A virtual table that can be accessed via SQL commands
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A virtual table that cannot be accessed via SQL commands
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There is no difference between a view and a table
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None of these
A
Correct answer
Explanation
A database view is a virtual table representing the result of a pre-defined SQL query. It does not store data physically but can be queried using standard SQL commands just like a normal table. Distractors are incorrect because views can be accessed via SQL, unlike tables which physically store data.