For Expert help and assignment handling,
1
WGU D426 Questions and Answers (100%
Correct Answers) Already Graded A+
A ____ is a column, or group of columns, used to identify a row. Ans:
Primary key
A ____ consists of a single column. Ans: Simple primary key
© 2026 Assignment Expert
A ____ key consists of multiple columns. Ans: Composite primary
All primary keys columns are necessary for uniqueness. When any
Guru01 - Stuvia
column is removed, the resulting simple or composite column is no longer
unique. Ans: Minimal
The ____ constraint in the CREATE TABLE statement names the table's
____. The ____ constraint ensures that a column or group of columns is
always unique and non-null. Ans: Primary key
An _____ is a numeric column that is assigned an automatically
incrementing value when a new row is inserted. Ans: Auto-increment
column
The ____ keyword defines an auto-increment column. It follows the
column's data type in a CREATE TABLE statement. Ans:
AUTO_INCREMENT
A ____ is a column, or group of columns, that refer to a primary key. Ans:
Foreign key
, For Expert help and assignment handling,
2
____ requires foreign key values must either be NULL or match some
value of the referenced primary key. Ans: Referential integrity
A ____ constraint is added to a CREATE TABLE statement with the ____
and REFERENCES keywords. Ans: Foreign key; references
A ____ foreign key is a simple or composite foreign key in which all
columns are NULL. Ans: Fully NULL
© 2026 Assignment Expert
____ is a relational rule that requires foreign key values to either be fully
NULL or match some primary key value. Ans: Referential integrity
____ rejects an insert, update, or delete that violates referential integrity.
Guru01 - Stuvia
Ans: RESTRICT
____ sets invalid foreign keys to NULL. Ans: SET NULL
____ sets invalid foreign keys to the foreign key default value. Ans: SET
DEFAULT
____ propagates primary key changes to foreign keys. Ans: CASCADE
Actions are specified in the optional ____ and ____ clauses of the
FOREIGN KEY constraint. ____ and ____ are followed by either RESTRICT,
SET NULL, SET DEFAULT, or CASCADE. Ans: ON UPDATE and ON DELETE
A ____ is a rule that governs allowable values in a database. ____ are
based on relational and business rules, and implemented with special
keywords in a CREATE TABLE statement. The database automatically
rejects insert, update, and delete statements that violate a constraint.
Ans: Constraint(s)
1
WGU D426 Questions and Answers (100%
Correct Answers) Already Graded A+
A ____ is a column, or group of columns, used to identify a row. Ans:
Primary key
A ____ consists of a single column. Ans: Simple primary key
© 2026 Assignment Expert
A ____ key consists of multiple columns. Ans: Composite primary
All primary keys columns are necessary for uniqueness. When any
Guru01 - Stuvia
column is removed, the resulting simple or composite column is no longer
unique. Ans: Minimal
The ____ constraint in the CREATE TABLE statement names the table's
____. The ____ constraint ensures that a column or group of columns is
always unique and non-null. Ans: Primary key
An _____ is a numeric column that is assigned an automatically
incrementing value when a new row is inserted. Ans: Auto-increment
column
The ____ keyword defines an auto-increment column. It follows the
column's data type in a CREATE TABLE statement. Ans:
AUTO_INCREMENT
A ____ is a column, or group of columns, that refer to a primary key. Ans:
Foreign key
, For Expert help and assignment handling,
2
____ requires foreign key values must either be NULL or match some
value of the referenced primary key. Ans: Referential integrity
A ____ constraint is added to a CREATE TABLE statement with the ____
and REFERENCES keywords. Ans: Foreign key; references
A ____ foreign key is a simple or composite foreign key in which all
columns are NULL. Ans: Fully NULL
© 2026 Assignment Expert
____ is a relational rule that requires foreign key values to either be fully
NULL or match some primary key value. Ans: Referential integrity
____ rejects an insert, update, or delete that violates referential integrity.
Guru01 - Stuvia
Ans: RESTRICT
____ sets invalid foreign keys to NULL. Ans: SET NULL
____ sets invalid foreign keys to the foreign key default value. Ans: SET
DEFAULT
____ propagates primary key changes to foreign keys. Ans: CASCADE
Actions are specified in the optional ____ and ____ clauses of the
FOREIGN KEY constraint. ____ and ____ are followed by either RESTRICT,
SET NULL, SET DEFAULT, or CASCADE. Ans: ON UPDATE and ON DELETE
A ____ is a rule that governs allowable values in a database. ____ are
based on relational and business rules, and implemented with special
keywords in a CREATE TABLE statement. The database automatically
rejects insert, update, and delete statements that violate a constraint.
Ans: Constraint(s)
