LATEST WGU C175/D426 DATA MANAGEMENT FOUNDATIONS OA EXAM ACTUAL EXAM 2 LATEST VERSIONS 300 QUESTIONS AND CORRECT VERIFIED ANSWERS WITH RATIONALES (100% CORRECT) A+ GRADED ASSURED

WGU C175/D426 DATA MANAGEMENT FOUNDATIONS OA
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EXAM -with 100% verified solutions-2026-2027 CORRECT AND
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VERIFIED ANSWERS)|ALREADY GRADED A+
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What does modality refer to? How does it appear on ER diagram? - ANSWER-
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Refers to the MINIMUM number of times an instance in one entity can be
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associated with instance of another entity (minima)
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Appears as a 0 or 1 on the relationship line, next to cardinality
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Define: Referential Integrity - ANSWER- Requires that ALL foreign key values
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must either be fully NULL or match some primary key value
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4 Ways Referential Integrity can be violated: - ANSWER- 1. Primary key is
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updated
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2. Foreign key is updated ht ht ht




3. Row containing primary key is DELETED
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4. Row containing foreign key is INSERTED
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4 Actions to Correct Referential Integrity Violation: - ANSWER- 1. RESTRICT -
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rejects an insert, update, or delete
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2. SET NULL - sets invalid foreign keys to null
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3. SET DEFAULT - sets invalid foreign keys to a default primary value
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4. CASCADE - propagates primary key changes to foreign keys ht ht ht ht ht ht ht ht




What is an important aspect to referential integrity? - ANSWER- reference to data
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in one relation is based on values in another relation
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,What is a broad definition of data? - ANSWER- Raw facts captured on printed or
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digital media
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What are data? - ANSWER- Facts that are collected and stored in a database system
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What is a determining characteristic of unstructured data? - ANSWER- It does not
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follow a data ht ht




model
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What is true about flat files? - ANSWER- - They contain no internal hierarchical
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organization
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How were data retrieved before database management systems? - ANSWER-
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Sequentially from simple files
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What is an attribute or group of attributes that uniquely identify a tuple in a
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relation? - ANSWER- Primary Key
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What is necessary for a primary key in one relation of a database to match with its
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corresponding foreign key in another relation of the same database? - ANSWER-
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A domain of values
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What uniquely identifies each entity in a collection of entities but is not the primary
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key? - ANSWER- Alternate Key
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What is the term for a set of columns in a table that can uniquely identify any
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record in that table without referring to other data? - ANSWER- Candidate Key
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What happens to the original data in database indexing? - ANSWER- It is copied to
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the index
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Why are indexes created in a physical database design? - ANSWER- To retrieve
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data DIRECTLY using a pointer
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Why is an index created on a database column? - ANSWER- To optimize data
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retrievals
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Define: Functional Dependency - ANSWER- Each value of a column relates to at
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MOST one value of another column
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Dependence of one column on another ht ht ht ht ht

,What term is used to describe: a value of one particular attribute associated with a
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specific single value of another attribute? - ANSWER- Functional Dependency
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Rules/Appearance of First Normal Form - ANSWER- - All non-key columns ht ht ht ht ht ht ht ht ht ht




depend on primary key
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- Each table cell contains one value
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- A table with no duplicate rows
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Rules/Appearance of Second Normal Form - ANSWER- - When all non-key ht ht ht ht ht ht ht ht ht ht




columns depend on the WHOLE primary key
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- Must be in 1NF
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- Non-key column can not depend on just one part of a composite key - a single
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primary key is automatically in 2NF
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Rules/Appearance of Third Normal Form - ANSWER- - All non-key columns ht ht ht ht ht ht ht ht ht ht




depend ONLY on the primary key
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- Tables are totally free of data redundancy
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What are the 4 ways that operational and analytical databases differ? - ANSWER-
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- Volatility
- Detail
- Scope
- History

Define: Volatility; How it applies to Operational? Analytical? - ANSWER- -
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Database updates in real time
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- Operational Data is Volatile ht ht ht




- Analytical Data is NOT Volatile ht ht ht ht




Define: Detail; How it applies to operational and analytical DB? - ANSWER- - A
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database that keeps record of individual transactions; line items
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- Operational: Detailed ht




- Analytical: Detailed ht




Define: Scope; How it applies to operational and analytical DB? - ANSWER- -
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How far a database can reach
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- Operational: incompatible ht




- Analytical: Enterprise-Wide/Summary ht

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