MIS 542 Chapter 6

Both is known as a minimum cardinality enforcement action and needs to be documented by the database development team are correct

A referential integrity constraint policy that guarantees that a row in a parent table always has a required entry in a child table ________.

cascading deletes

A referential integrity constraint policy that insures that all rows containing a foreign key value in a table are eliminated from the table when the row containing the corresponding primary key value in a parent table is eliminated from the database is called ________.

cascading updates

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 ________.

Both Define referential integrity constraint from child to parent and Make foreign key NOT NULL are correct

For the M-O (parent mandatory, child optional) case, what action(s) should be taken to ensure minimum cardinality is maintained?

representing intersection relationships

Four uses for ID-dependent entities include all of the following except ________.

Creating a primary key

In a relational database design, all relationships are expressed by ________.

Both cannot be represented in a relational design and require application logic to determine which subtypes correspond to a specific supertype instance are correct

In a supertype-subtype structure, discriminator attributes ________.

a binary relationship includes a set of value combinations that must all occur in a ternary relationship

The binary constraint must cover indicates that ________.

a binary relationship includes value combinations that must not occur in a ternary relationship

The binary constraint must not indicates that ________.

create a table for each entity

The first step in transforming an extended E-R model into a relational database design is to ---.

primary key

The identifier of the entity becomes the --- of the corresponding table.

the key of either table may be placed as a foreign key into the other

When representing a 1:1 relationship in a relational database design, ________.

the parent is always on the one side of the "one-to-many" relationship

When representing a one-to-many relationship in a relational database design, ________.

when the child entity is ID-dependent

When transforming an E-R 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 ________.

parent updates to cascade

When transforming an ID-dependent E-R data model relationship into a relational database design, the referential integrity constraints should allow ________.

Create constraints and triggers

Which of the following is not a step in the database design process?

Both Since it is a recursive relationship, an intersection table is not needed and The foreign keys in the intersection table can't refer to the same attribute in the parent table are correct.

Which of the following is not true about N:M recursive relationships?

it must have a default value specified

Which of the following is not true about a NULL attribute?

All attributes of the supertype are added to the subtype relations.

Which of the following is not true about representing subtypes in a relational database design?

They are non-unique within a table (not true)

Which of the following is not true about surrogate keys?

a composite of several long attributes

Which of the following is not true for an ideal primary key?

It can be expressed directly in a relational model.

Which of the following is not true of a MUST constraint?

When the relationship is 1:N, a new table must be defined to represent the relationship.

Which of the following is not true of recursive relationships?

Each attribute of an entity becomes a(n) --- of a table.

column

the key contains a lengthy text field

A surrogate key should be considered when ---.

The intersection table is ID-dependent on one of the parents

In many-to-many relationships between strong entities in a relational database design, which of the following is not true?

the keys of both tables are placed in a third table

In many-to-many relationships in a relational database design, ________.

represent relationships where the child identifier does not include the key of the parent

In relational database design, ID-dependent entities are not used to ________.

an intersection table which has 1:N relationships with the two tables

Many-to-many relationships are represented by ________.

the key of the parent is placed as a foreign key into the child

To represent a one-to-many relationship in a relational database design, ________.