DATA MANAGEMENT - FOUNDATIONS -
D426 WGU: EXAM, 2025/2026 WITH
CORRECT/ACCURATE ANSWERS
Data - CORRECT ANSWERS- Numeric, textual, visual, or audio
information that describes real-world systems. It is collected and
processed to aid in a variety of tasks.
Analog Data - CORRECT ANSWERS- Most common before
computers. Audio was recorded as vibrations impressed on vinyl
disks.
Normalization - CORRECT ANSWERS- Eliminates redundancy by
decomposing a table into two or more tables in higher normal
form.
Denormalization - CORRECT ANSWERS- Intentionally introducing
redundancy by merging tables.
Single-Level Index - CORRECT ANSWERS- What type of index am
I?
A file containing column values, along with pointers to rows
containing the column value.
,Multi-Column Index - CORRECT ANSWERS- What type of index am
I?
Each index entry is a composite of values from all indexed
columns.
Dense Index - CORRECT ANSWERS- What type of index am I?
Contains an entry for every table row.
Sparse Index - CORRECT ANSWERS- What type of index am I?
Contains an entry for every table block.
Table scan - CORRECT ANSWERS- A database operation that
reads table blocks directly, without accessing an index.
Index scan - CORRECT ANSWERS- A database operation that
reads index blocks sequentially, in order to locate the needed
table blocks.
Hit Ratio - CORRECT ANSWERS- The percentage of table rows
selected by a query.
, Primary Index/Clustering Index - CORRECT ANSWERS- What type
of index am I?
An index on a sort column.
Secondary Index/Nonclustering Index - CORRECT ANSWERS-
What type of index am I?
An index that is not on the sort column.
Binary Search - CORRECT ANSWERS- The database repeatedly
splits the index in two until it finds the entry containing the search
value.
Multi-Level Index - CORRECT ANSWERS- What type of index am I?
Stores column values and row pointers in a hierarchy.
B+Tree - CORRECT ANSWERS- All indexed values appear in the
bottom level. Pointers to table blocks appear only in the bottom
level. Since some indexed values also appear in higher levels,
values are occasionally repeated in the index.
B-Tree - CORRECT ANSWERS- If an indexed value appears in a
higher level, the value is not repeated at lower levels. Instead, a
D426 WGU: EXAM, 2025/2026 WITH
CORRECT/ACCURATE ANSWERS
Data - CORRECT ANSWERS- Numeric, textual, visual, or audio
information that describes real-world systems. It is collected and
processed to aid in a variety of tasks.
Analog Data - CORRECT ANSWERS- Most common before
computers. Audio was recorded as vibrations impressed on vinyl
disks.
Normalization - CORRECT ANSWERS- Eliminates redundancy by
decomposing a table into two or more tables in higher normal
form.
Denormalization - CORRECT ANSWERS- Intentionally introducing
redundancy by merging tables.
Single-Level Index - CORRECT ANSWERS- What type of index am
I?
A file containing column values, along with pointers to rows
containing the column value.
,Multi-Column Index - CORRECT ANSWERS- What type of index am
I?
Each index entry is a composite of values from all indexed
columns.
Dense Index - CORRECT ANSWERS- What type of index am I?
Contains an entry for every table row.
Sparse Index - CORRECT ANSWERS- What type of index am I?
Contains an entry for every table block.
Table scan - CORRECT ANSWERS- A database operation that
reads table blocks directly, without accessing an index.
Index scan - CORRECT ANSWERS- A database operation that
reads index blocks sequentially, in order to locate the needed
table blocks.
Hit Ratio - CORRECT ANSWERS- The percentage of table rows
selected by a query.
, Primary Index/Clustering Index - CORRECT ANSWERS- What type
of index am I?
An index on a sort column.
Secondary Index/Nonclustering Index - CORRECT ANSWERS-
What type of index am I?
An index that is not on the sort column.
Binary Search - CORRECT ANSWERS- The database repeatedly
splits the index in two until it finds the entry containing the search
value.
Multi-Level Index - CORRECT ANSWERS- What type of index am I?
Stores column values and row pointers in a hierarchy.
B+Tree - CORRECT ANSWERS- All indexed values appear in the
bottom level. Pointers to table blocks appear only in the bottom
level. Since some indexed values also appear in higher levels,
values are occasionally repeated in the index.
B-Tree - CORRECT ANSWERS- If an indexed value appears in a
higher level, the value is not repeated at lower levels. Instead, a
