DBS Theory

Physical data independence means:

B. Physical storage can change without changing logical schema

Which is NOT guaranteed in the relational model?

C. No attribute ordering

Relational algebra truths (multiple select):

A. Procedural
B. Has six basic operators
D. Equivalent in power to tuple/domain relational calculus

A candidate key means:

B. No proper subset determines R

Total participation means:

A. Every entity participates at least once

Normalization goals (multiple select):

A. Reduce redundancy
B. Lossless decomposition
D. Reduce anomalies

BCNF condition for FD α→β:

C. α is a superkey

3NF allows:

C. Each attribute in β−α is contained in a candidate key

Meaning of MVD Y↠Z:

B. Z‑values associated with Y are independent of other attributes

1NF enforces:

B. Atomic attribute domains