CH 6 SG
The ideal primary key is ________.
short, numeric, and fixed
The binary constraint MUST NOT indicates that _____
a binary relationship includes value combinations that must not occur in a ternary relationship
When transforming an IDdependent ER data model relationship into a relational database design and the parent entity has a surrogate primary key and the child entity has a data identifier, then the primary key of the child table should be _____
either the parent's surrogate key + the child's data key or the parent's surrogate key + a surrogate key in the child will work, but method the parent's surrogate key + a surrogate key in the child is preferable
When transforming an IDdependent ER data model relationship into a relational database design, the referential integrity constraints should allow ____
parent updates to cascade
The identifier of the entity becomes the ________ of the corresponding table.
primary key
One of the important properties of a column is whether or not it is ____
required
In manytomany relationships in a relational database design, ________.
the intersection table is IDdependent on one of the parents and the intersection table is IDdependent on both of the parents
When representing a 1:1 relationship in a relational database design, ________.
the key of either table may be placed as a foreign key into the other
To represent a onetomany relationship in a relational database design, ________.
the key of the parent is placed as a foreign key into the child
In manytomany relationships in a relational database design, ________.
the keys of both tables are placed in a third table and the keys of both tables are joined into a composite key
When representing a onetomany relationship in a relational database design, ________.
the parent is always on the one side of the "onetomany" relationship
When transforming an IDdependent ER data model relationship into a relational database design and the child entity is designed to use a surrogate key, then ____
the relationship changes to a nonIDdependent relationship
When transforming an ER data model into a relational database design, the key of the parent entity should be placed as part of the primary key into the child entity _____
when the child entity is IDdependent
In relational database design, IDdependent entities are used to _______
All of these.
Manytomany relationships are represented by ___
an intersection table which has 1:N relationships with the two tables
A referential integrity constraint policy that insures that foreign key values in a table are correctly maintained when there is a change to the primary key value in the parent table is called ________.
cascading updates
Each attribute of an entity becomes a(n) ________ of a table.
column
To which of the following actions are referential integrity constraints not applied?
create
The first step in transforming an extended ER model into a relational database design is to ________.
create a table for each entity
A referential integrity constraint policy that guarantees that a row in a parent table always has a required entry in a child table ________.
is known as a minimum cardinality enforcement action and needs to be documented by the database development team