domain
In data modeling, the construct used to organize and describe an attribute's set of possible values
superkey
An attribute or attributes
... [Show More] 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
natural join
Join type that returns only the rows with matching values in the matching columns; the matching columns must have the same names and similar data types
left, right, full
Name the three types of outer joins
ALL
This operator can be used to compare something to every returned row of a subquery
ANY
This operator can be used to compare something to a list of values and return any rows that satisfy the criteria
correlated subquery
A subquery that executes once for each row in the outer query
UNION
SQL statement that combines rows from two or more queries without including duplicate rows, as long as the queries return the same # of attributes and similar data types
UNION ALL
SQL statement similar to UNION but retaining duplicate rows [Show Less]