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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a. Defining part numbers
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b. Modeling organization structures
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c. Tracking perpetual inventory
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d. All the above
D
Correct answer
Explanation
The Oracle Inventory module is comprehensive: it defines items (part numbers with attributes), models organization and warehouse structures, and tracks perpetual inventory transactions. Option D correctly encompasses all these functions.
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Materials Requirement Planning (MRP)
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Replenishment Counting, Kanban, Min-Max Planning
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Safety Stock
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None of the above
B
Correct answer
Explanation
Oracle Inventory supports multiple replenishment methods including Replenishment Counting, Kanban, and Min-Max Planning. MRP is a separate planning methodology, and Safety Stock is a setting, not a replenishment method per se.
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Data about the Data
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Machine level Data
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Characteristics of Data
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Relationship between Data
A
Correct answer
Explanation
Metadata is defined as "data about the data" - information that describes other data's characteristics, structure, or context (like file size, creation date, column names). It is not machine-level data (raw bits), not just characteristics (a subset), and not relationships between data (which would be schema/foreign keys). Option A is the standard definition.
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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
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None
B
Correct answer
Explanation
Dimension tables store descriptive attributes about business entities, providing context for facts in the fact table. They contain relatively static data like customer names, product categories, or geographic regions. Option A incorrectly describes measures (not dimensions), while option C describes fact tables which contain numeric additive data.
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Tables typically contain facts and primary keys to the dimension tables
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Tables typically contain facts/numerical values and are 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 numerical measurements (facts) and foreign keys that link to dimension tables. Each row typically represents a business event or transaction. Option A is incorrect because fact tables use foreign keys (not primary keys) to reference dimension tables. Option C describes a variation but doesn't capture the essential structure.
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Attribute
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Fact
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Functions and Operators
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Filter
A,B,C
Correct answer
Explanation
In MicroStrategy schema design, Attributes define descriptive data elements, Facts contain numerical metrics for analysis, and Functions/Operators provide calculation capabilities for data manipulation. These three are fundamental schema objects. Filters are report-level objects used to restrict data display, not schema objects.
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Source Systems
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Data Warehouse
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Metadata
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Microstrategy applications
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All of the above
E
Correct answer
Explanation
A complete MicroStrategy BI architecture requires source systems (operational databases), data warehouse (central repository), metadata (definitions and mappings), and MicroStrategy applications (reporting interface). All four components are essential for the full architecture.
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Report Filter
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View Filter
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Prompt
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None
B
Correct answer
Explanation
View Filters are applied at the report level after data retrieval, allowing filtering without affecting the warehouse query. Report Filters apply at the warehouse level (in the WHERE clause), Prompts enable user selection, and the question specifically asks for report-level filtering.
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The ability to add attributes and metrics to a report definition without having them be displayed on the template
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Users can drag and drop additional objects onto the template of the report without generating new SQL or querying the data warehouse
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Derived metrics and View Filters
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All of the above
D
Correct answer
Explanation
MicroStrategy OLAP Services provides three key capabilities: adding objects to report definition without displaying them (option A), drag-and-drop without new SQL queries (option B), and support for derived metrics with View Filters (option C). All three are features of OLAP Services.
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allow to customize the SQL that Microstrategy generates
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they can be applied at DB level, report level and metric levels
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help to improve the performance of the report
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All of the above
D
Correct answer
Explanation
VLDB properties in MicroStrategy are performance optimization settings that allow customization of generated SQL, can be applied at database, report, or metric levels, and help improve report performance by controlling how queries are executed against large databases.
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Work Classes
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Data Classes
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Rule Classes
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All of the Above
D
Correct answer
Explanation
Pega automatically maintains history tables for work items (History-Work-), configurations or data instances (History-Data-), and rule modifications (History-Rule-). Therefore, history records are created across all of these categories, making the options specifying individual classes too narrow and All of the Above correct.
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In Memory Cache of the XML of a frequently accessed rule
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Disk based cache of the XML of a frequently accessed rule
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First Use Assembly cache
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Cache of the generated and instantiated rule instance
A
Correct answer
Explanation
The Rule Instance Cache is an in-memory cache that stores the XML representation of frequently accessed rules to improve performance. It caches the rule definition (XML), not the generated code or instantiated objects. This is distinct from First Use Assembly cache which caches generated Java code.
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pzInsStream
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PzPVStream
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pzObjStream
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pzRefStream
B
Correct answer
Explanation
Pega stores the serialized XML or JSON representation of a rule or work instance in a binary large object (BLOB) column named pzPVStream. Other options like pzInsStream, pzObjStream, and pzRefStream are incorrect column names that do not store the main instance BLOB payload.
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Object level locks persist for longer than database level lock and prevent two users from making changes to the record simultaneously
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Database locks are held for a longer duration than object locks
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Both
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None
A
Correct answer
Explanation
Object-level locks are higher-level constructs that persist longer than database locks, specifically designed to prevent concurrent modifications by multiple users. Database locks are lower-level, shorter-duration mechanisms for maintaining data integrity at the storage level.
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Classifies incoming data into groups
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Computes totals and other summary
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Functions for each group
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All of the above
D
Correct answer
Explanation
The Aggregator stage performs all three functions: it classifies incoming data into groups based on key specifications, computes aggregate functions (sums, counts, averages, etc.) for each group, and applies various summary functions to the grouped data.