WGU C175/D426 DATA MANAGEMENT FOUNDATIONS
OA EXAM NEWEST 2025 ACTUAL EXAM 2 LATEST
VERSIONS 300 QUESTIONS AND CORRECT
DETAILED ANSWERS WITH RATIONALES (100%
CORRECT AND VERIFIED ANSWERS) ALREADY
GRADED A+
)(*&!@
Modality - 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 #$(*&^
relationship line, next to cardinality.
#$%^(*
Referential Integrity - ANSWER: Requires that ALL foreign key values must either be &^%$!
fully NULL or match some primary key value.
@#$%^
Ways Referential Integrity can be violated - 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 - 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.
Important aspect of Referential Integrity - ANSWER: Reference to data in one relation is
based on values in another relation.
Broad definition of data - ANSWER: Raw facts captured on printed or digital media.
Data - ANSWER: Facts that are collected and stored in a database system.
Determining characteristic of unstructured data - ANSWER: It does not follow a data
model.
Flat files - ANSWER: They contain no internal hierarchical organization.
Data retrieval before database management systems - ANSWER: Sequentially from
simple files.
Primary Key - ANSWER: An attribute or group of attributes that uniquely identify a tuple
in a relation.
Foreign Key matching - 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.
,WGU C175/D426 DATA MANAGEMENT FOUNDATIONS
OA EXAM NEWEST 2025 ACTUAL EXAM 2 LATEST
VERSIONS 300 QUESTIONS AND CORRECT
DETAILED ANSWERS WITH RATIONALES (100%
CORRECT AND VERIFIED ANSWERS) ALREADY
GRADED A+
)(*&!@
Alternate Key - ANSWER: What uniquely identifies each entity in a collection of entities
but is not the primary key. #$(*&^
#$%^(*
Candidate Key - ANSWER: A set of columns in a table that can uniquely identify any
record in that table without referring to other data. &^%$!
Database indexing - ANSWER: The original data is copied to the index. @#$%^
&*
Indexes in physical database design - ANSWER: To retrieve data DIRECTLY using a
pointer.
Index creation on a database column - ANSWER: To optimize data retrievals.
Functional Dependency - ANSWER: Each value of a column relates to at MOST one
value of another column.
Rules/Appearance of First Normal Form - 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 - 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 - ANSWER: - All non-key columns depend
ONLY on the primary key - Tables are totally free of data redundancy.
Differences between operational and analytical databases - ANSWER: - Volatility -
Detail - Scope - History.
Volatility - ANSWER: Database updates in real time. Operational Data is Volatile.
Analytical Data is NOT Volatile.
Detail in databases - ANSWER: - A database that keeps record of individual
transactions; line items - Operational: Detailed - Analytical: Detailed.
Scope in databases - ANSWER: - How far a database can reach - Operational:
incompatible - Analytical: Enterprise-Wide/Summary.
, WGU C175/D426 DATA MANAGEMENT FOUNDATIONS
OA EXAM NEWEST 2025 ACTUAL EXAM 2 LATEST
VERSIONS 300 QUESTIONS AND CORRECT
DETAILED ANSWERS WITH RATIONALES (100%
CORRECT AND VERIFIED ANSWERS) ALREADY
GRADED A+
)(*&!@
History in databases - ANSWER: - Whether DB is current or tracks all data -
Operational: Current only - Analytical: Tracks trends. #$(*&^
#$%^(*
Data warehouse refresh process - ANSWER: 1. Extraction 2. Cleanse 3. Integrate 4.
Restructure 5. Load. &^%$!
Extraction in ETL - ANSWER: Data extracted and put into staging area. @#$%^
&*
Cleanse in ETL - ANSWER: Errors are eliminated from data; standard abbreviations
applied.
Integrate in ETL - ANSWER: Data is put into a uniform structure; Data converted to
uniform structure.
Restructure in ETL - ANSWER: Data is structured in a design that is optimal for
analysis.
Load in ETL - ANSWER: Data is loaded to the data warehouse.
Issue focused on 'Load' component of ETL - ANSWER: Monitor refreshing volume and
frequency.
Step in ETL Process where raw data is aggregated - ANSWER: Transformation steps.
Data mining activities - ANSWER: 1. Clustering & Segmentation 2. Classification 3.
Estimation 4. Prediction 5. Affinity Grouping 6. Description.
Clustering & Segmentation - ANSWER: Taking large entity and dividing into smaller
groups of entities. Useful when unsure of what looking for.
Classification (Data Mining) - ANSWER: Organizing data into predefined classes.
Estimation (Data Mining) - ANSWER: Assigning a numeric value to an object.
Prediction (Data Mining) - ANSWER: Classifying objects according to an expected
future behavior.
Affinity Grouping - ANSWER: Evaluating relationships between data elements that
demonstrate some kind of affinity between objects.
OA EXAM NEWEST 2025 ACTUAL EXAM 2 LATEST
VERSIONS 300 QUESTIONS AND CORRECT
DETAILED ANSWERS WITH RATIONALES (100%
CORRECT AND VERIFIED ANSWERS) ALREADY
GRADED A+
)(*&!@
Modality - 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 #$(*&^
relationship line, next to cardinality.
#$%^(*
Referential Integrity - ANSWER: Requires that ALL foreign key values must either be &^%$!
fully NULL or match some primary key value.
@#$%^
Ways Referential Integrity can be violated - 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 - 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.
Important aspect of Referential Integrity - ANSWER: Reference to data in one relation is
based on values in another relation.
Broad definition of data - ANSWER: Raw facts captured on printed or digital media.
Data - ANSWER: Facts that are collected and stored in a database system.
Determining characteristic of unstructured data - ANSWER: It does not follow a data
model.
Flat files - ANSWER: They contain no internal hierarchical organization.
Data retrieval before database management systems - ANSWER: Sequentially from
simple files.
Primary Key - ANSWER: An attribute or group of attributes that uniquely identify a tuple
in a relation.
Foreign Key matching - 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.
,WGU C175/D426 DATA MANAGEMENT FOUNDATIONS
OA EXAM NEWEST 2025 ACTUAL EXAM 2 LATEST
VERSIONS 300 QUESTIONS AND CORRECT
DETAILED ANSWERS WITH RATIONALES (100%
CORRECT AND VERIFIED ANSWERS) ALREADY
GRADED A+
)(*&!@
Alternate Key - ANSWER: What uniquely identifies each entity in a collection of entities
but is not the primary key. #$(*&^
#$%^(*
Candidate Key - ANSWER: A set of columns in a table that can uniquely identify any
record in that table without referring to other data. &^%$!
Database indexing - ANSWER: The original data is copied to the index. @#$%^
&*
Indexes in physical database design - ANSWER: To retrieve data DIRECTLY using a
pointer.
Index creation on a database column - ANSWER: To optimize data retrievals.
Functional Dependency - ANSWER: Each value of a column relates to at MOST one
value of another column.
Rules/Appearance of First Normal Form - 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 - 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 - ANSWER: - All non-key columns depend
ONLY on the primary key - Tables are totally free of data redundancy.
Differences between operational and analytical databases - ANSWER: - Volatility -
Detail - Scope - History.
Volatility - ANSWER: Database updates in real time. Operational Data is Volatile.
Analytical Data is NOT Volatile.
Detail in databases - ANSWER: - A database that keeps record of individual
transactions; line items - Operational: Detailed - Analytical: Detailed.
Scope in databases - ANSWER: - How far a database can reach - Operational:
incompatible - Analytical: Enterprise-Wide/Summary.
, WGU C175/D426 DATA MANAGEMENT FOUNDATIONS
OA EXAM NEWEST 2025 ACTUAL EXAM 2 LATEST
VERSIONS 300 QUESTIONS AND CORRECT
DETAILED ANSWERS WITH RATIONALES (100%
CORRECT AND VERIFIED ANSWERS) ALREADY
GRADED A+
)(*&!@
History in databases - ANSWER: - Whether DB is current or tracks all data -
Operational: Current only - Analytical: Tracks trends. #$(*&^
#$%^(*
Data warehouse refresh process - ANSWER: 1. Extraction 2. Cleanse 3. Integrate 4.
Restructure 5. Load. &^%$!
Extraction in ETL - ANSWER: Data extracted and put into staging area. @#$%^
&*
Cleanse in ETL - ANSWER: Errors are eliminated from data; standard abbreviations
applied.
Integrate in ETL - ANSWER: Data is put into a uniform structure; Data converted to
uniform structure.
Restructure in ETL - ANSWER: Data is structured in a design that is optimal for
analysis.
Load in ETL - ANSWER: Data is loaded to the data warehouse.
Issue focused on 'Load' component of ETL - ANSWER: Monitor refreshing volume and
frequency.
Step in ETL Process where raw data is aggregated - ANSWER: Transformation steps.
Data mining activities - ANSWER: 1. Clustering & Segmentation 2. Classification 3.
Estimation 4. Prediction 5. Affinity Grouping 6. Description.
Clustering & Segmentation - ANSWER: Taking large entity and dividing into smaller
groups of entities. Useful when unsure of what looking for.
Classification (Data Mining) - ANSWER: Organizing data into predefined classes.
Estimation (Data Mining) - ANSWER: Assigning a numeric value to an object.
Prediction (Data Mining) - ANSWER: Classifying objects according to an expected
future behavior.
Affinity Grouping - ANSWER: Evaluating relationships between data elements that
demonstrate some kind of affinity between objects.
