D426 PRACTICE TEST EXAM:
2025/2026, WITH CORRECT/ACCURATE
ANSWERS
A ____ join returns rows with matching values and includes all
rows from both tables (T1 and T2) with unmatched values.
a. natural
b. cross
c. full outer
d. left outer - CORRECT ANSWERS- c. full outer
During which step in the extract, transform, load (ETL) process
are raw data sets aggregated?
a. Transformation
b. Extraction
c. Loading
d. Denormalization - CORRECT ANSWERS- a. Transformation
During the transformation step, a series of rules or functions is
applied to the extracted data and can involve transformation such
,as data summations, data encoding, data merging, data splitting,
data calculations, and create of surrogate keys.
Which is an important issue associated with the loading
component of extract, transform, load (ETL)?
a. Mapping keys from one system to another
b. Monitor refreshing volume and frequency
c. Determining the content of the data
d. Denormalizing and renormalizing data - CORRECT ANSWERS-
b. Monitor refreshing volume and frequency
The loading component of ETL is centered on moving the
transformed data into the data warehouse. The critical issues
include the following:
→Target dependencies, such as where and on how many
machines the repository lives, and the specifics of loading data
into that platform.
→Refresh volume and frequency, such as whether the data
warehouse is to be loaded on an incremental basis, whether data
is forwarded to the repository as a result of triggered transaction
events, or whether all the data is periodically loaded into the
warehouse in the form of a full refresh.
Which statement will remove all rows from the Materials table
that have a Status value of 'Obsolete' but do not have a value for
the VendorID column?
, a. DELETE Materials
WHERE Status = 'Obsolete' OR VendorID IS NULL
b. DELETE
FROM Materials
WHERE Status = 'Obsolete' AND VendorID IS NULL
c. DELETE MaterialID, Description, Status, VendorID
FROM Materials
WHERE Status = 'Obsolete' AND VendorID IS NULL
d. DELETE FROM Materials
WHERE Status = 'Obsolete'
WHERE VendorID IS NULL - CORRECT ANSWERS- b.
DELETE
FROM Materials
WHERE Status = 'Obsolete' AND VendorID IS NULL
The TestScores table has these characteristics:
Each student has a unique StudentID that references the Students
table.
2025/2026, WITH CORRECT/ACCURATE
ANSWERS
A ____ join returns rows with matching values and includes all
rows from both tables (T1 and T2) with unmatched values.
a. natural
b. cross
c. full outer
d. left outer - CORRECT ANSWERS- c. full outer
During which step in the extract, transform, load (ETL) process
are raw data sets aggregated?
a. Transformation
b. Extraction
c. Loading
d. Denormalization - CORRECT ANSWERS- a. Transformation
During the transformation step, a series of rules or functions is
applied to the extracted data and can involve transformation such
,as data summations, data encoding, data merging, data splitting,
data calculations, and create of surrogate keys.
Which is an important issue associated with the loading
component of extract, transform, load (ETL)?
a. Mapping keys from one system to another
b. Monitor refreshing volume and frequency
c. Determining the content of the data
d. Denormalizing and renormalizing data - CORRECT ANSWERS-
b. Monitor refreshing volume and frequency
The loading component of ETL is centered on moving the
transformed data into the data warehouse. The critical issues
include the following:
→Target dependencies, such as where and on how many
machines the repository lives, and the specifics of loading data
into that platform.
→Refresh volume and frequency, such as whether the data
warehouse is to be loaded on an incremental basis, whether data
is forwarded to the repository as a result of triggered transaction
events, or whether all the data is periodically loaded into the
warehouse in the form of a full refresh.
Which statement will remove all rows from the Materials table
that have a Status value of 'Obsolete' but do not have a value for
the VendorID column?
, a. DELETE Materials
WHERE Status = 'Obsolete' OR VendorID IS NULL
b. DELETE
FROM Materials
WHERE Status = 'Obsolete' AND VendorID IS NULL
c. DELETE MaterialID, Description, Status, VendorID
FROM Materials
WHERE Status = 'Obsolete' AND VendorID IS NULL
d. DELETE FROM Materials
WHERE Status = 'Obsolete'
WHERE VendorID IS NULL - CORRECT ANSWERS- b.
DELETE
FROM Materials
WHERE Status = 'Obsolete' AND VendorID IS NULL
The TestScores table has these characteristics:
Each student has a unique StudentID that references the Students
table.
