WGU C170 Data Management - Applications
domain - ✔✔In data modeling, the construct used to organize and describe an attribute's set of
possible values
superkey - ✔✔An attribute or attributes that uniquely identify each entity in a table. Any composite
key with this is also this.
candidate key - ✔✔A minimal superkey; that is, a key that does not contain a subset of attributes
that is itself a superkey
entity integrity - ✔✔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 - ✔✔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 - ✔✔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 - ✔✔A detailed system data dictionary that describes all objects in a database
homonym - ✔✔The use of the same name to label different attributes, much like similar-sounding
words with different meanings
synonym - ✔✔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 - ✔✔Any candidate key must have these two constraints enforced
cardinality - ✔✔Term for how many instances of one object are related to instances of another
object (maximum)
, modality - ✔✔Term for whether an instance of a specific entity is optional or mandatory in a
relationship (minimum)
connectivity - ✔✔Term for the classification of the relationship between entities. Classifications
include 1:1, 1:M, and M:N
CREATE SCHEMA AUTHORIZATION - ✔✔SQL command to create a database schema
DEFAULT - ✔✔SQL option to define a default value for a column (when no value is given)
CHECK - ✔✔SQL command to validate data in an attribute, used during table column creation
CREATE TABLE AS - ✔✔SQL command to create a new table based on a query in the user's database
schema
HAVING - ✔✔SQL option that restricts a selection of grouped rows based on a condition
EXISTS - ✔✔SQL option that checks whether a subquery returns any rows
DECIMAL - ✔✔SQL data type like the NUMBER specification, but the storage length is a minimum
specification
True - ✔✔True or false: if an INSERT or SELECT command is embedded inside a program for later use,
the attribute list should always be used, as the table may change over time
inner join - ✔✔A join operation in which only rows that meet a given criterion are selected. The most
common type of join
outer join - ✔✔A join operation that produces a table in which all unmatched pairs are retained;
unmatched values in the related table are left null
cross join - ✔✔A join operation that returns the Cartesian product of two sets or tables
domain - ✔✔In data modeling, the construct used to organize and describe an attribute's set of
possible values
superkey - ✔✔An attribute or attributes that uniquely identify each entity in a table. Any composite
key with this is also this.
candidate key - ✔✔A minimal superkey; that is, a key that does not contain a subset of attributes
that is itself a superkey
entity integrity - ✔✔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 - ✔✔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 - ✔✔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 - ✔✔A detailed system data dictionary that describes all objects in a database
homonym - ✔✔The use of the same name to label different attributes, much like similar-sounding
words with different meanings
synonym - ✔✔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 - ✔✔Any candidate key must have these two constraints enforced
cardinality - ✔✔Term for how many instances of one object are related to instances of another
object (maximum)
, modality - ✔✔Term for whether an instance of a specific entity is optional or mandatory in a
relationship (minimum)
connectivity - ✔✔Term for the classification of the relationship between entities. Classifications
include 1:1, 1:M, and M:N
CREATE SCHEMA AUTHORIZATION - ✔✔SQL command to create a database schema
DEFAULT - ✔✔SQL option to define a default value for a column (when no value is given)
CHECK - ✔✔SQL command to validate data in an attribute, used during table column creation
CREATE TABLE AS - ✔✔SQL command to create a new table based on a query in the user's database
schema
HAVING - ✔✔SQL option that restricts a selection of grouped rows based on a condition
EXISTS - ✔✔SQL option that checks whether a subquery returns any rows
DECIMAL - ✔✔SQL data type like the NUMBER specification, but the storage length is a minimum
specification
True - ✔✔True or false: if an INSERT or SELECT command is embedded inside a program for later use,
the attribute list should always be used, as the table may change over time
inner join - ✔✔A join operation in which only rows that meet a given criterion are selected. The most
common type of join
outer join - ✔✔A join operation that produces a table in which all unmatched pairs are retained;
unmatched values in the related table are left null
cross join - ✔✔A join operation that returns the Cartesian product of two sets or tables
