WGU C803 : DATA TYPES AND
STRUCTURES COMPREHENSIVE STUDY
GUIDE 2026 FULL QUESTIONS AND
SOLUTIONS GRADED A+
◍ Every part of a tree spawns how many children?.
Answer: 0 or more
◍ There are 3 items in a stack, the next line of code is "push('item');". How
many items are now in the stack?.
Answer: 4
◍ Which type of function works by breaking down large problem into smaller
and smaller chunks?.
Answer: O(log n)
◍ Define the delete rule SET-TO-NUL
L. .
Answer: If the delete rule between the two relations is SET-TO-NULL and
an attempt is made to delete a record on the "one side" of the one-to-many
relationship, that record will be deleted and the matching foreign key values
in the records on the "many side" of the relationship will be set to
null.Essentially, it's exactly like the CASCADE delete option, but instead of
completely deleting all possible values, the values are set to NULL instead.
◍ In which of the normal forms should every non-key attribute be fully
functionally dependent on the entire key of a table?.
Answer: Second form
◍ SELECT command.
Answer: - Data retrieval in SQL is accomplished with the SELECT
, command.
◍ Equijoin.
Answer: Combines two or more tables based on a column that is common to
the tables. Example: Joining Client and Salesman tables that both contain
the SalesmanID column which have the exact same values.
◍ A tree that maintains the simple property that a node's key is less than or
equal to the node's childrens' keys..
Answer: min heap
◍ What is used for populating summaries or any cube dimensions that can be
performed at the staging area (ETL)?.
Answer: Aggregation
◍ What method removes a value from a dictionary?.
Answer: remove();
◍ OLAP.
Answer: OLAP (Online Analytical Processing) is both a process of viewing
comparative metrics via a multidimensional analysis of data and the
infrastructure to support that process.
◍ What are the values of Business Intelligence?.
Answer: - Financial value associated w/ increased profitability.- Productivity
value associated with increased throughput.- Trust value (customer,
employee, supplier satisfaction) as well as increased confidence in
forecasting.- Risk value - decreased risk associated with decision making
◍ Referential Integrity.
Answer: Referential integrity is a database concept that ensures that
relationships between tables remain consistent.
◍ A Last-in, First-out (LIFO) data container.
Answer: Stack
◍ Which type of function allows for items to be added or removed from the
beginning or end?.
, Answer: Doubly Ended Queue (deque)
◍ Which activity groups data members that have similarities?.
Answer: Clustering
◍ Cartesian product.
Answer: Usually the result of a missing join condition or a method of
expanding the data of 1 table by the number of rows in the second table.
◍ In a Hash Table keys need to be ______..
Answer: unique
◍ * in the SELECT clause.
Answer: - It indicates that all attributes of the selected row are to be
retrieved
◍ A modulo hash function for a 50 entry hash table is: key % _____.
Answer: 50
◍ Association Rules.
Answer: Association rules specify a relation between attributes that appears
more frequently than expected if the attributes were independent.
◍ A data structure in which each node stores data and has up to two children,
known as a left child and a right child..
Answer: binary tree
◍ A list that builds on the singly linked list by adding reverse iteration..
Answer: Doubly Linked List
◍ A functions whose cost scales logarithmically with the input size.
Answer: O(log n)
◍ Write the SQL query to "Find the commission percentage and year of hire of
salesperson 186":.
Answer: SELECT COMMPERCT, YEARHIREFROM
SALESPERSONWHERE SPNUM=186;
◍ An example of this type of function is when there is a nested loop that
STRUCTURES COMPREHENSIVE STUDY
GUIDE 2026 FULL QUESTIONS AND
SOLUTIONS GRADED A+
◍ Every part of a tree spawns how many children?.
Answer: 0 or more
◍ There are 3 items in a stack, the next line of code is "push('item');". How
many items are now in the stack?.
Answer: 4
◍ Which type of function works by breaking down large problem into smaller
and smaller chunks?.
Answer: O(log n)
◍ Define the delete rule SET-TO-NUL
L. .
Answer: If the delete rule between the two relations is SET-TO-NULL and
an attempt is made to delete a record on the "one side" of the one-to-many
relationship, that record will be deleted and the matching foreign key values
in the records on the "many side" of the relationship will be set to
null.Essentially, it's exactly like the CASCADE delete option, but instead of
completely deleting all possible values, the values are set to NULL instead.
◍ In which of the normal forms should every non-key attribute be fully
functionally dependent on the entire key of a table?.
Answer: Second form
◍ SELECT command.
Answer: - Data retrieval in SQL is accomplished with the SELECT
, command.
◍ Equijoin.
Answer: Combines two or more tables based on a column that is common to
the tables. Example: Joining Client and Salesman tables that both contain
the SalesmanID column which have the exact same values.
◍ A tree that maintains the simple property that a node's key is less than or
equal to the node's childrens' keys..
Answer: min heap
◍ What is used for populating summaries or any cube dimensions that can be
performed at the staging area (ETL)?.
Answer: Aggregation
◍ What method removes a value from a dictionary?.
Answer: remove();
◍ OLAP.
Answer: OLAP (Online Analytical Processing) is both a process of viewing
comparative metrics via a multidimensional analysis of data and the
infrastructure to support that process.
◍ What are the values of Business Intelligence?.
Answer: - Financial value associated w/ increased profitability.- Productivity
value associated with increased throughput.- Trust value (customer,
employee, supplier satisfaction) as well as increased confidence in
forecasting.- Risk value - decreased risk associated with decision making
◍ Referential Integrity.
Answer: Referential integrity is a database concept that ensures that
relationships between tables remain consistent.
◍ A Last-in, First-out (LIFO) data container.
Answer: Stack
◍ Which type of function allows for items to be added or removed from the
beginning or end?.
, Answer: Doubly Ended Queue (deque)
◍ Which activity groups data members that have similarities?.
Answer: Clustering
◍ Cartesian product.
Answer: Usually the result of a missing join condition or a method of
expanding the data of 1 table by the number of rows in the second table.
◍ In a Hash Table keys need to be ______..
Answer: unique
◍ * in the SELECT clause.
Answer: - It indicates that all attributes of the selected row are to be
retrieved
◍ A modulo hash function for a 50 entry hash table is: key % _____.
Answer: 50
◍ Association Rules.
Answer: Association rules specify a relation between attributes that appears
more frequently than expected if the attributes were independent.
◍ A data structure in which each node stores data and has up to two children,
known as a left child and a right child..
Answer: binary tree
◍ A list that builds on the singly linked list by adding reverse iteration..
Answer: Doubly Linked List
◍ A functions whose cost scales logarithmically with the input size.
Answer: O(log n)
◍ Write the SQL query to "Find the commission percentage and year of hire of
salesperson 186":.
Answer: SELECT COMMPERCT, YEARHIREFROM
SALESPERSONWHERE SPNUM=186;
◍ An example of this type of function is when there is a nested loop that
