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 set of technolgies that enable customer relationships
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A set of technologies that enable the managment of unstructured content within the organization
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A set of technologies that enable knowledge management within the organization
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A set of technologies that enable the managment of structured content within the organization
B,C
Correct answer
Explanation
ECM means managing unstructured content (B) and enables knowledge management (C) within the organization. Option A describes CRM, and D is incorrect because ECM specifically handles UNSTRUCTURED content, not structured data.
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Version Control for managing multiple versions of a document
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Access Control for documents for security and compliance
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Search and Retrieval of content based on key words
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OCR / ICR for character recognition from Images
A,B,C
Correct answer
Explanation
A Document Management System (DMS) focuses on the lifecycle of electronic documents. Key features include Version Control (tracking changes), Access Control (security), and Search/Retrieval. While OCR/ICR is often used to ingest paper documents into a DMS, it is considered a capture technology rather than a core management feature of the DMS itself.
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Unmount the shared file system such as a Network Attached Storage (NAS) where thetransaction log is stored
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Restart the deployment manager and node agents who manage the transaction log
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Verify another running cluster member has access to the transaction log
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Reconnect the database where the transaction log is stored
C
Correct answer
Explanation
When a cluster member crashes, locks held by its transactions must be released by another member with access to the transaction log for recovery. The transaction log contains the state of in-flight transactions. Options A, B, and D don't address transaction log access which is required for lock recovery in clustered environments.
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Tabular Data
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Summary Data
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Graphical Data
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None of the above
A
Correct answer
Explanation
List data containers are specifically designed to display repeating, columnar data in tabular format. They show data rows with multiple columns, making them ideal for detailed listings. Summary data involves aggregations and would use summary containers, while graphical data requires chart or graphic containers.
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Requirement gathering
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Data modeling
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Data profiling
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Data mining
D
Correct answer
Explanation
Building a data warehouse involves Requirement gathering, Data modeling, and Data profiling as core steps. Data mining is an analytical technique performed on data, not a step in building the warehouse infrastructure itself.
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Data Profiling
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Data Modelling
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Data Integration
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Data Staging
C
Correct answer
Explanation
Data Integration is the process of extracting data from multiple sources, cleansing it, applying business rules, and loading it into a unified target like a data warehouse. Data Profiling is analysis, Data Modelling is design, and Data Staging is temporary storage.
B
Correct answer
Explanation
Data modeling is a broad concept that includes conceptual, logical, and physical modeling of data. Dimensional modeling is a specific data modeling technique optimized for data warehousing and business intelligence (using facts and dimensions). They are not the same.
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Conceptual modelling
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Physical modelling
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Logical modelling
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None of the above
D
Correct answer
Explanation
All three listed techniques - Conceptual modelling, Logical modelling, and Physical modelling - are valid ER modelling techniques. Therefore 'None of the above' is the correct answer since all options ARE techniques.
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Global Temporary
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Permanent
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Derived
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Volatile
A
Correct answer
Explanation
In Teradata, a Global Temporary Table (GTT) stores its definition (DDL) in the data dictionary, which is shared by all users. However, the data inserted into the table is materialized in temp space and is private to the session, meaning users do not share data.
A
Correct answer
Explanation
DBCS uses two bytes to represent each character, enabling support for large character sets like Japanese, Chinese, or Korean. This is necessary because single-byte encoding can only represent 256 characters, which is insufficient for languages with thousands of characters.
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The granularity has to same as the business process
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The granularity must be an aggregate of the actual granularity of the business
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The granularity is decided based on the business needs and requirements from the data warehouse/mart
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None of the above
C
Correct answer
Explanation
Fact table granularity is determined by business requirements and the level of detail needed for analysis. It should align with what the business needs from the data warehouse, not necessarily match the raw business process granularity (too detailed) or be an aggregate (too summarized).
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Store the business Id of the dimension in the fact table, when the dimension is updated, update the dimension
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Add surrogate keys in the dimension and fact, create a new row in the dimension when it is updated
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Create a new dimension table
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Add another column to the dimension table to store the update
B
Correct answer
Explanation
To preserve historical changes in a dimension (Slowly Changing Dimension Type 2), you add surrogate keys to the dimension and fact tables, and insert a new row in the dimension table whenever an update occurs.
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Yes, as long as the granularity is the same
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No, different facts should be stored in different tables
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Depends on individual measure
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Can't say
A
Correct answer
Explanation
Two facts based on the same dimensions can be stored in the same fact table as long as they share the exact same level of detail (granularity).
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As long as the aggregate facts refer to keys in appropriate layer in the dimsension
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Multiple aggregate levels can be stored in different tables
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Aggregated facts should not be stored in the physical tables, they must always be calculated on the fly
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A and B
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All of the above
A,B,D
Correct answer
Explanation
Aggregate facts at different levels can share the same physical table as long as each fact references dimension keys at its appropriate grain. Alternatively, different aggregate levels can be stored in separate tables for performance or clarity. Option C is incorrect because pre-aggregated facts are commonly stored in physical tables rather than calculated on the fly.
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retrieve the table by using the flashback feature
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restore all the data files from last Sunday's backup and then perform a time-based recovery
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restore all the data files from last Sunday's backup and then perform a log sequence recovery
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restore all the data files from last Sunday's backup and then perform a cancel-based recovery
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restore from last Sunday's backup only data files that belong to the tablespace in which the table was stored and then perform a complete recovery
B
Correct answer
Explanation
Since the table was dropped with the PURGE option, it bypasses the Recycle Bin, meaning flashback drop cannot be used. You must restore all data files from the last backup and perform a time-based incomplete recovery to a point just before 8:00 a.m.