WGU C175/D426 DATA MANAGEMENT FOUNDATIONS OA
2025 UPDATED EXAM | ACTUAL EXAM 2 LATEST VERSIONS 400
QUESTIONS AND CORRECT VERIFIED ANSWERS WITH
RATIONALES (100% CORRECT) A+ GRADED ASSURED !!
Where does affinity grouping occur in data mining? - ANSWER-
Between objects
What is the uniquely identifiable element about which data can
be categorized in
an entity-relationship diagram? - ANSWER-
Entity types
Which 3 rules for referential integrity are provided by modern
relational database management systems? - ANSWER-Insert
Update
Delete
Define: Unique Attribute - ANSWER-Each attribute instance
describes only ONE
entity
instance
,What does the DISTINCT clause do? - ANSWER-Returns only
unique or 'distinct'
values; Filters Data
Results
What does the ORDER BY clause do? - ANSWER-Modifies
presentation of data
results
Which SQL statement alphabetizes customer names within the
same satellite-
office city? - ANSWER-ORDER BY SATCITY,
CUSTNAME
What is a heap file? - ANSWER-A file where records can be
placed anywhere in
the
memory
What is a hash file? - ANSWER-A file that uses Hash function
computation on some fields of the records, and the result of that
computation determines where the record is stored
, What are the different types of major Joins? - ANSWER-
- LEFT JOIN
- RIGHT
JOIN
- INNER JOIN
- FULL JOIN
What do joins do? - ANSWER-Joins *usually* compare the
foreign key of one table to the primary key of another table (but
can join any columns) - joining together data from two tables
into one table
LEFT JOIN - ANSWER-selects all the rows from the left table, and
only matching
rows from the right
table
RIGHT JOIN - ANSWER-selects all the rows from the right
table, and only
matching rows from the
left table
OUTER JOIN - ANSWER-Any join that selects unmatched rows;
LEFT, RIGHT,
2025 UPDATED EXAM | ACTUAL EXAM 2 LATEST VERSIONS 400
QUESTIONS AND CORRECT VERIFIED ANSWERS WITH
RATIONALES (100% CORRECT) A+ GRADED ASSURED !!
Where does affinity grouping occur in data mining? - ANSWER-
Between objects
What is the uniquely identifiable element about which data can
be categorized in
an entity-relationship diagram? - ANSWER-
Entity types
Which 3 rules for referential integrity are provided by modern
relational database management systems? - ANSWER-Insert
Update
Delete
Define: Unique Attribute - ANSWER-Each attribute instance
describes only ONE
entity
instance
,What does the DISTINCT clause do? - ANSWER-Returns only
unique or 'distinct'
values; Filters Data
Results
What does the ORDER BY clause do? - ANSWER-Modifies
presentation of data
results
Which SQL statement alphabetizes customer names within the
same satellite-
office city? - ANSWER-ORDER BY SATCITY,
CUSTNAME
What is a heap file? - ANSWER-A file where records can be
placed anywhere in
the
memory
What is a hash file? - ANSWER-A file that uses Hash function
computation on some fields of the records, and the result of that
computation determines where the record is stored
, What are the different types of major Joins? - ANSWER-
- LEFT JOIN
- RIGHT
JOIN
- INNER JOIN
- FULL JOIN
What do joins do? - ANSWER-Joins *usually* compare the
foreign key of one table to the primary key of another table (but
can join any columns) - joining together data from two tables
into one table
LEFT JOIN - ANSWER-selects all the rows from the left table, and
only matching
rows from the right
table
RIGHT JOIN - ANSWER-selects all the rows from the right
table, and only
matching rows from the
left table
OUTER JOIN - ANSWER-Any join that selects unmatched rows;
LEFT, RIGHT,
