WGU C170 EXAM PREP TEST BANK
VERIFIED QUESTIONS AND CORRECT
ANSWERS
●● superkey
Answer: An attribute or attributes that uniquely identify each entity in a
table. Any composite key with this is also this.
●● candidate key
Answer: A minimal superkey; that is, a key that does not contain a
subset of attributes that is itself a superkey
●● entity integrity
Answer: The property of a relational table that guarantees each entity
has a unique value in a primary key and that the key has no null values
●● referential integrity
Answer: A condition by which a dependent table's foreign key must have
either a null entry or a matching entry in the related table
●● data dictionary
, Answer: A DBMS component that stores metadata. It contains the data
definition & their characteristics and relationships; may also include data
external to the DBMS
●● system catalog
Answer: A detailed system data dictionary that describes all objects in a
database
●● homonym
Answer: The use of the same name to label different attributes, much
like similar-sounding words with different meanings
●● synonym
Answer: The use of different names to identify the same object, such as
an entity, an attribute, or a relationship. These should generally be
avoided.
●● not null and unique
Answer: Any candidate key must have these two constraints enforced
●● cardinality
Answer: Term for how many instances of one object are related to
instances of another object (maximum)
VERIFIED QUESTIONS AND CORRECT
ANSWERS
●● superkey
Answer: An attribute or attributes that uniquely identify each entity in a
table. Any composite key with this is also this.
●● candidate key
Answer: A minimal superkey; that is, a key that does not contain a
subset of attributes that is itself a superkey
●● entity integrity
Answer: The property of a relational table that guarantees each entity
has a unique value in a primary key and that the key has no null values
●● referential integrity
Answer: A condition by which a dependent table's foreign key must have
either a null entry or a matching entry in the related table
●● data dictionary
, Answer: A DBMS component that stores metadata. It contains the data
definition & their characteristics and relationships; may also include data
external to the DBMS
●● system catalog
Answer: A detailed system data dictionary that describes all objects in a
database
●● homonym
Answer: The use of the same name to label different attributes, much
like similar-sounding words with different meanings
●● synonym
Answer: The use of different names to identify the same object, such as
an entity, an attribute, or a relationship. These should generally be
avoided.
●● not null and unique
Answer: Any candidate key must have these two constraints enforced
●● cardinality
Answer: Term for how many instances of one object are related to
instances of another object (maximum)
