17 August 2026
WGU C175/D426 DATA MANAGEMENT FOUNDATIONS
OA EXAM NEWEST 2026/2027 ACTUAL EXAM LATEST
VERSIONS 300 QUESTIONS AND CORRECT DETAILED
ANSWERS WITH RATIONALES (100% CORRECT AND
VERIFIED ANSWERS)|ALREADY GRADED A+
What does Modality refers to? How does it appear on ER diagram? - correct answer-Refers to the
MINIMUM number of times an instance in one entity can be associated with instance of another
entity (minima). Appears as a 0 or 1 on the relationship line, next to cardinality.
Define: Referential Integrity - correct answer-Requires that ALL foreign key values must either be
fully NULL or match some primary key value.
4 Ways Referential Integrity can be violated - correct answer-1. Primary key is updated 2. Foreign key
is updated 3. Row containing primary key is DELETED 4. Row containing foreign key is INSERTED.
Actions to Correct Referential Integrity Violation - correct answer-1. RESTRICT - rejects an insert,
update, or delete 2. SET NULL - sets invalid foreign keys to null 3. SET DEFAULT - sets invalid foreign
keys to a default primary value 4. CASCADE - propagates primary key changes to foreign keys.
What is an Important aspect of Referential Integrity - correct answer-Reference to data in one
relation is based on values in another relation.
What is Broad definition of data - correct answer-Raw facts captured on printed or digital media.
What Data - correct answer-Facts that are collected and stored in a database system.
Determining characteristic of unstructured data - correct answer-It does not follow a data model.
Flat files - correct answer-They contain no internal hierarchical organization.
Data retrieval before database management systems - correct answer-Sequentially from simple files.
Primary Key - correct answer-An attribute or group of attributes that uniquely identify a tuple in a
relation.
,30 July 2026
Foreign Key matching - correct answer-A domain of values is necessary for a primary key in one
relation of a database to match with its corresponding foreign key in another relation of the same
database.
Alternate Key - correct answer-What uniquely identifies each entity in a collection of entities but is
not the primary key.
Candidate Key - correct answer-A set of columns in a table that can uniquely identify any record in
that table without referring to other data.
Database indexing - correct answer-The original data is copied to the index.
Indexes in physical database design - correct answer-To retrieve data DIRECTLY using a pointer.
Index creation on a database column - correct answer-To optimize data retrievals.
Functional Dependency - correct answer-Each value of a column relates to at MOST one value of
another column.
Rules/Appearance of First Normal Form - correct answer-- All non-key columns depend on primary
key - Each table cell contains one value - A table with no duplicate rows.
Rules/Appearance of Second Normal Form - correct answer-- When all non-key columns depend on
the WHOLE primary key - Must be in 1NF - Non-key column can not depend on just one part of a
composite key - a single primary key is automatically in 2NF.
Rules/Appearance of Third Normal Form - correct answer-- All non-key columns depend ONLY on the
primary key - Tables are totally free of data redundancy.
Differences between operational and analytical databases - correct answer-- Volatility - Detail -
Scope - History.
Volatility - correct answer-Database updates in real time. Operational Data is Volatile. Analytical
Data is NOT Volatile.
, 30 July 2026
Detail in databases - correct answer-- A database that keeps record of individual transactions; line
items - Operational: Detailed - Analytical: Detailed.
Scope in databases - correct answer-- How far a database can reach - Operational: incompatible -
Analytical: Enterprise-Wide/Summary.
History in databases - correct answer-- Whether DB is current or tracks all data - Operational:
Current only - Analytical: Tracks trends.
Data warehouse refresh process - correct answer-1. Extraction 2. Cleanse 3. Integrate 4. Restructure
5. Load.
Extraction in ETL - correct answer-Data extracted and put into staging area.
Cleanse in ETL - correct answer-Errors are eliminated from data; standard abbreviations applied.
Integrate in ETL - correct answer-Data is put into a uniform structure; Data converted to uniform
structure.
Restructure in ETL - correct answer-Data is structured in a design that is optimal for analysis.
Load in ETL - correct answer-Data is loaded to the data warehouse.
Issue focused on 'Load' component of ETL - correct answer-Monitor refreshing volume and
frequency.
Step in ETL Process where raw data is aggregated - correct answer-Transformation steps.
Data mining activities - correct answer-1. Clustering & Segmentation 2. Classification 3. Estimation 4.
Prediction 5. Affinity Grouping 6. Description.
Clustering & Segmentation - correct answer-Taking large entity and dividing into smaller groups of
entities. Useful when unsure of what looking for.
WGU C175/D426 DATA MANAGEMENT FOUNDATIONS
OA EXAM NEWEST 2026/2027 ACTUAL EXAM LATEST
VERSIONS 300 QUESTIONS AND CORRECT DETAILED
ANSWERS WITH RATIONALES (100% CORRECT AND
VERIFIED ANSWERS)|ALREADY GRADED A+
What does Modality refers to? How does it appear on ER diagram? - correct answer-Refers to the
MINIMUM number of times an instance in one entity can be associated with instance of another
entity (minima). Appears as a 0 or 1 on the relationship line, next to cardinality.
Define: Referential Integrity - correct answer-Requires that ALL foreign key values must either be
fully NULL or match some primary key value.
4 Ways Referential Integrity can be violated - correct answer-1. Primary key is updated 2. Foreign key
is updated 3. Row containing primary key is DELETED 4. Row containing foreign key is INSERTED.
Actions to Correct Referential Integrity Violation - correct answer-1. RESTRICT - rejects an insert,
update, or delete 2. SET NULL - sets invalid foreign keys to null 3. SET DEFAULT - sets invalid foreign
keys to a default primary value 4. CASCADE - propagates primary key changes to foreign keys.
What is an Important aspect of Referential Integrity - correct answer-Reference to data in one
relation is based on values in another relation.
What is Broad definition of data - correct answer-Raw facts captured on printed or digital media.
What Data - correct answer-Facts that are collected and stored in a database system.
Determining characteristic of unstructured data - correct answer-It does not follow a data model.
Flat files - correct answer-They contain no internal hierarchical organization.
Data retrieval before database management systems - correct answer-Sequentially from simple files.
Primary Key - correct answer-An attribute or group of attributes that uniquely identify a tuple in a
relation.
,30 July 2026
Foreign Key matching - correct answer-A domain of values is necessary for a primary key in one
relation of a database to match with its corresponding foreign key in another relation of the same
database.
Alternate Key - correct answer-What uniquely identifies each entity in a collection of entities but is
not the primary key.
Candidate Key - correct answer-A set of columns in a table that can uniquely identify any record in
that table without referring to other data.
Database indexing - correct answer-The original data is copied to the index.
Indexes in physical database design - correct answer-To retrieve data DIRECTLY using a pointer.
Index creation on a database column - correct answer-To optimize data retrievals.
Functional Dependency - correct answer-Each value of a column relates to at MOST one value of
another column.
Rules/Appearance of First Normal Form - correct answer-- All non-key columns depend on primary
key - Each table cell contains one value - A table with no duplicate rows.
Rules/Appearance of Second Normal Form - correct answer-- When all non-key columns depend on
the WHOLE primary key - Must be in 1NF - Non-key column can not depend on just one part of a
composite key - a single primary key is automatically in 2NF.
Rules/Appearance of Third Normal Form - correct answer-- All non-key columns depend ONLY on the
primary key - Tables are totally free of data redundancy.
Differences between operational and analytical databases - correct answer-- Volatility - Detail -
Scope - History.
Volatility - correct answer-Database updates in real time. Operational Data is Volatile. Analytical
Data is NOT Volatile.
, 30 July 2026
Detail in databases - correct answer-- A database that keeps record of individual transactions; line
items - Operational: Detailed - Analytical: Detailed.
Scope in databases - correct answer-- How far a database can reach - Operational: incompatible -
Analytical: Enterprise-Wide/Summary.
History in databases - correct answer-- Whether DB is current or tracks all data - Operational:
Current only - Analytical: Tracks trends.
Data warehouse refresh process - correct answer-1. Extraction 2. Cleanse 3. Integrate 4. Restructure
5. Load.
Extraction in ETL - correct answer-Data extracted and put into staging area.
Cleanse in ETL - correct answer-Errors are eliminated from data; standard abbreviations applied.
Integrate in ETL - correct answer-Data is put into a uniform structure; Data converted to uniform
structure.
Restructure in ETL - correct answer-Data is structured in a design that is optimal for analysis.
Load in ETL - correct answer-Data is loaded to the data warehouse.
Issue focused on 'Load' component of ETL - correct answer-Monitor refreshing volume and
frequency.
Step in ETL Process where raw data is aggregated - correct answer-Transformation steps.
Data mining activities - correct answer-1. Clustering & Segmentation 2. Classification 3. Estimation 4.
Prediction 5. Affinity Grouping 6. Description.
Clustering & Segmentation - correct answer-Taking large entity and dividing into smaller groups of
entities. Useful when unsure of what looking for.
