1Z0-006 Relational Data Model 5

Question 1

First Normal Form (1NF) requires that all column values in a table must be:

Accepted Answer

Atomic (indivisible, single-valued)

Answer

1NF requires each cell to hold a single, atomic value; no repeating groups or multi-valued attributes are allowed.

Question 2

A self-referencing (recursive) foreign key means a table's foreign key references:

Accepted Answer

Its own primary key in the same table

Answer

A self-referencing foreign key points back to the primary key of the same table, commonly used to model hierarchies like an employee-manager relationship.

Question 3

Which SQL command removes all rows from a table quickly without logging individual row deletions and cannot be rolled back by default in Oracle?

Accepted Answer

TRUNCATE

Answer

TRUNCATE removes all rows using a DDL operation that deallocates data pages; it cannot be rolled back because it does not generate per-row undo logs.

Question 4

Which type of integrity ensures that a foreign key value either matches an existing primary key value or is NULL?

Accepted Answer

Referential integrity

Answer

Referential integrity guarantees that every foreign key value references a valid primary key in the parent table or is NULL.

Question 5

In the Entity-Relationship model, which symbol on a crow's foot diagram represents 'one and only one'?

Accepted Answer

Single vertical line

Answer

A single vertical line (or perpendicular stroke) in crow's foot notation represents a cardinality of exactly one.

(1Z0-006) Oracle Database Foundations Associate Practice Test

(1Z0-006) Oracle Database Foundations Associate Practice Test

1Z0-006 Relational Data Model 5