Section 9
A barrred Relationship will
result in a Foreign Key column that also is part of:
The
Primary Key (*)
The
Check Constraint
The
Table Name
The Column
Name
Two entities A and B have an
optional (A) to Mandatory (B) One-to-One relationship. When they are
transformed, the Foreign Key(s) is placed on:
The
table B (*)
Nowhere,
One-to-One relationships are not transformed.
The
table A
Both
tables A and B get a new column and a Foreign Key.
One-to-One relationships are
transformed into Check Constraints in the tables created at either end of that
relationship. True or False?
True
False
(*)
In a physical model, many to
many relationships are resolved via a structure called a(n): ________________
Supertype
Intersection
Entity
Subtype
Intersection
Table (*)
The explanation below is an
example of which constraint type?
The value in the dept_no column of the EMPLOYEES table must
match a value in the dept_no column in the DEPARTMENTS table.
Entity
integrity
User-defined
integrity
Referential
integrity (*)
Column
integrity
Column integrity refers to
Columns
always having values
Columns
always containing positive numbers
Columns
always containing text data less than 255 characters
Columns
always containing values consistent with the defined data format (*)
Foreign keys cannot be null
when
It
contains three or more columns
It
refers to the same table
It is
part of a primary key (*)
It
refers to another table
The explanation below is an
example of which constraint type?
A column must contain only values consistent with the
defined data format of the column
Column
integrity (*)
User-defined
integrity
Referential
integrity
Entity
integrity
In a physical data model, a
relationship is represented as a combination of: (Choose Two)
Foreign
Key (*)
Primary
Key or Unique Key (*)
Check
Constraint or Unique Key
Column
Attributes become columns in a
database table. True or False?
True
(*)
False
In a
physical data model, an attribute becomes a _____________.
Constraint
Table
Column
(*)
Foreign
Key
In an Oracle database, why would
the following table name not be allowed 'EMPLOYEE JOBS'?
EMPLOYEE
is a reserved word
JOBS is
a reserved word
You
cannot have spaces between words in a table name (*)
The
database does not understand all capital letters
When translating an arc
relationship to a physical design, you must turn the arc relationships into
foreign keys. What additional step must you take with the created foreign keys
to ensure the exclusivity principle of arc relationships? (Assume that you are
implementing an Exclusive Design) (Choose Two)
Make
all relationships mandatory
Make
all relationships optional (*)
Create
an additional check constraint to verify that one foreign key is populated and
the others are not (*)
All the
above
When mapping supertypes,
relationships at the supertype level transform as usual. Relationships at
subtype level are implemented as foreign keys, but the foreign key columns all
become mandatory. True or False?
True
False
(*)
An "Arc Implementation"
can be done just like any other Relationship - you simply add the required
Foreign Keys. True or False?
True
False
(*)
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