Chapter 10 Study Questions Flashcards
A table in a relational database represents an object or ______.
entity
Within each table, each column stores one item of information or _________.
attribute
Each table row stores one occurrence, or ________, of the entity.
instance
The _______ key for a table uniquely identifies each row. It should be persistent and minimal.
primary
To implement a one-to-many relationship between tables, add a _______ key on the “many” side.
foreign
A many-to-many relationship between two tables is implemented with a _______ table.
linking table
___________ _________ means that the relationships between tables are maintained correctly (i.e. a table with foreign key values have matching key vales in the related table).
Referential integrity
If referential integrity is not enforced and a row is deleted from the primary key (or parent) table that has related rows in the foreign key table are said to be ________.
orphaned
_____________ is a formal process used to separate data in a data structure into separate tables. The purpose of this process is to reduce data redundancy.
Normalization
With an ____________ data structure, a table can contain information about two or more entities, repeating columns, and data that is repeated in two or more rows.
unnormalized
In a __________ ____ _________, each table contains information about a single entity, and each piece of information is stored in exactly one place.
normalized data structure
To normalize a data structure, apply the ______ _____ in sequence.
normal forms
An _____ is a structure that provides for locating one or more rows directly.
index
Without an index, a database management system has to perform a _____ ____ which involves searching through the entire table.
table scan
A _________ index consists of two or more columns.
composite
When normalizing a data structure, if the value stored at the intersection of each row and column is a scalar variable, and there are no repeating columns, the relation is in _____ ______ ____.
first normal form
The normal form where every non-key column is dependent on the entire primary key is termed ______ ______ ____.
second normal form
If every non-key column is dependent only on primary key, that is a non-key column is not a determinant, the relation is in _____ ______ ____.
third normal form
When normalized into ______-___ or _____ ______ ____, every constraint on the relationship is dependent only on key constraints and domain constraints.
domain-key or sixth normal form
A ______ is the set of allowable values for a column.
domain
