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WGU
WGU D426: OBJECTIVE ASSESSMENT EXAM QUESTIONS
WITH CORRECT VERIFIED ANSWERS LATEST UPDATE
(2024/2025) GUARANTEED PASS
Foreign Key - ANS ✓Is a column, or group of columns, that refer to a primary
key. An empty circle (○) represents foreign keys in table diagrams, and an arrow
leads to the referenced primary key.
When a ________ _____ constraint is specified, the database rejects insert,
update, and delete statements that violate referential integrity.
Referential integrity requires ________ ____ values must either be NULL or
match some value of the referenced primary key.
RESTRICT - ANS ✓________ rejects an insert, update, or delete that violates
referential integrity.
CASCADE - ANS ✓Propagates primary key changes to foreign keys.
Constraint - ANS ✓A __________ is a rule that governs allowable values in a
database based on relational and business rules.
UNIQUE (Constraint) - ANS ✓The _______ constraint ensures that values in a
column, or group of columns, are NEVER REPEATED.
CHECK (Constraint) - ANS ✓The _______ constraint specifies an expression on
one or more columns of a table.
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Adding and Dropping Constraints - ANS ✓Constraints are added and dropped
with the ALTER TABLE Table Name followed by an ADD, DROP, or CHANGE
clause.
BETWEEN (Operator) - ANS ✓The ________ operator provides an alternative way
to determine if a value is between two other values.
LIKE (Operator) - ANS ✓The _____ operator, when used in a WHERE clause,
matches text against a pattern using the two wildcard characters % and _.
ORDER BY (Clause) - ANS ✓The _____ ___ clause orders selected rows by one or
more columns in ascending (alphabetic or increasing) order. The DESC keyword
with the ORDER BY clause orders rows in descending order.
ABS(n) (Function) - ANS ✓Returns the absolute value of n. Distance from zero.
Always a positive number or zero.
LOWER(s) (Function) - ANS ✓Returns the lowercase "s". Or any specified
characters.
TRIM(s) (Function) - ANS ✓Returns the string "s" without leading and trailing
spaces
HOUR(t)
MINUTE(t)
SECOND(t)
(Function) - ANS ✓Returns the hour, minute, or second from time t
Aggregate (Function) - ANS ✓COUNT() counts the number of rows in the set.
MIN() finds the minimum value in the set.
MAX() finds the maximum value in the set.
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SUM() sums all the values in the set.
AVG() computes the arithmetic mean of all the values in the set.
HAVING (Clause) - ANS ✓The HAVING clause is used with the GROUP BY clause
to filter group results.
JOIN - ANS ✓A _____ is a SELECT statement that combines data from two tables,
known as the left table and right table, into a single result. The tables are
combined by comparing columns from the left and right tables, usually with the =
operator.
AS (Alias) - ANS ✓A column name can be replaced with an alias. The alias
follows the column name, separated by an optional AS keyword.
INNER JOIN - ANS ✓Selects only matching left and right table rows.
FULL JOIN - ANS ✓Selects all left and right table rows, regardless of match.
LEFT JOIN - ANS ✓Selects all left table rows, but only matching right table rows.
RIGHT JOIN - ANS ✓Selects all right table rows, but only matching left table
rows.
OUTER JOIN - ANS ✓Any join that selects unmatched rows, including left, right,
and full joins.
UNION (Keyword) - ANS ✓The ______ keyword combines the two results into one
table.
EQUIJOIN - ANS ✓An ___________ compares columns of two tables with the =
operator. This is the most common type of join.
WGU D426
WGU
WGU D426: OBJECTIVE ASSESSMENT EXAM QUESTIONS
WITH CORRECT VERIFIED ANSWERS LATEST UPDATE
(2024/2025) GUARANTEED PASS
Foreign Key - ANS ✓Is a column, or group of columns, that refer to a primary
key. An empty circle (○) represents foreign keys in table diagrams, and an arrow
leads to the referenced primary key.
When a ________ _____ constraint is specified, the database rejects insert,
update, and delete statements that violate referential integrity.
Referential integrity requires ________ ____ values must either be NULL or
match some value of the referenced primary key.
RESTRICT - ANS ✓________ rejects an insert, update, or delete that violates
referential integrity.
CASCADE - ANS ✓Propagates primary key changes to foreign keys.
Constraint - ANS ✓A __________ is a rule that governs allowable values in a
database based on relational and business rules.
UNIQUE (Constraint) - ANS ✓The _______ constraint ensures that values in a
column, or group of columns, are NEVER REPEATED.
CHECK (Constraint) - ANS ✓The _______ constraint specifies an expression on
one or more columns of a table.
WGU D426
, 2
WGU
Adding and Dropping Constraints - ANS ✓Constraints are added and dropped
with the ALTER TABLE Table Name followed by an ADD, DROP, or CHANGE
clause.
BETWEEN (Operator) - ANS ✓The ________ operator provides an alternative way
to determine if a value is between two other values.
LIKE (Operator) - ANS ✓The _____ operator, when used in a WHERE clause,
matches text against a pattern using the two wildcard characters % and _.
ORDER BY (Clause) - ANS ✓The _____ ___ clause orders selected rows by one or
more columns in ascending (alphabetic or increasing) order. The DESC keyword
with the ORDER BY clause orders rows in descending order.
ABS(n) (Function) - ANS ✓Returns the absolute value of n. Distance from zero.
Always a positive number or zero.
LOWER(s) (Function) - ANS ✓Returns the lowercase "s". Or any specified
characters.
TRIM(s) (Function) - ANS ✓Returns the string "s" without leading and trailing
spaces
HOUR(t)
MINUTE(t)
SECOND(t)
(Function) - ANS ✓Returns the hour, minute, or second from time t
Aggregate (Function) - ANS ✓COUNT() counts the number of rows in the set.
MIN() finds the minimum value in the set.
MAX() finds the maximum value in the set.
WGU D426
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WGU
SUM() sums all the values in the set.
AVG() computes the arithmetic mean of all the values in the set.
HAVING (Clause) - ANS ✓The HAVING clause is used with the GROUP BY clause
to filter group results.
JOIN - ANS ✓A _____ is a SELECT statement that combines data from two tables,
known as the left table and right table, into a single result. The tables are
combined by comparing columns from the left and right tables, usually with the =
operator.
AS (Alias) - ANS ✓A column name can be replaced with an alias. The alias
follows the column name, separated by an optional AS keyword.
INNER JOIN - ANS ✓Selects only matching left and right table rows.
FULL JOIN - ANS ✓Selects all left and right table rows, regardless of match.
LEFT JOIN - ANS ✓Selects all left table rows, but only matching right table rows.
RIGHT JOIN - ANS ✓Selects all right table rows, but only matching left table
rows.
OUTER JOIN - ANS ✓Any join that selects unmatched rows, including left, right,
and full joins.
UNION (Keyword) - ANS ✓The ______ keyword combines the two results into one
table.
EQUIJOIN - ANS ✓An ___________ compares columns of two tables with the =
operator. This is the most common type of join.
WGU D426
