CH 6 SG

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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


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