Question at position 36 In the figure shown below, which of the following business rules would apply? Each warehouse can be supplied with any number of parts from more than one vendor, and each warehouse could be supplied with no parts. Each part must be supplied by exactly one vendor to any number of warehouses. VENDOR is not allowed.Each vendor can supply many parts to any number of warehouses, but need not supply any parts.

Question

BlackTom AI · Accepted Answer

Crow’s-foot notation: a circle denotes optional (0), a crow’s foot denotes “many” (*), and a single straight line denotes “one” (1). The diagram’s relationship symbols therefore determine cardinality and optionality.

1) Relevant knowledge points and concepts
- Crow’s foot = many; single line = one; circle = optional (zero allowed); perpendicular/short line = mandatory (must exist).
- An associative entity (SUPPLY SCHEDULE) linking three entities indicates that vendors, parts and warehouses are related through supply schedule records; cardinalities on each connector show how many schedules relate to each entity and whether that relationship is optional.

2) Step-by-step reasoning
- Look at the connector between VENDOR and SUPPLY SCHEDULE: the symbol on the VENDOR side indicates that one vendor can be associated with many supply-schedule records (crow’s foot from the schedule toward vendor side), while the circle/optional marker on the vendor end of the relationship shows that a vendor need not participate in any schedule (0 allowed). Combined, that yields 0..* for vendor → supply schedules.
- The SUPPLY SCHEDULE connects to WAREHOUSE with a crow’s foot on the warehouse side, indicating many warehouses can be involved across schedules; the absence of a mandatory mark on the vendor side (and an optional circle) shows vendors are not required to supply parts.
- Therefore a single vendor can supply many parts (via many supply-schedule records) to any number of warehouses, but a vendor may also supply none.

3) Intermediate “calculation”/interpretation steps
- Vendor cardinality: 0..* (optional, many).
- Supply schedule acts as the many-side connector, enabling many-to-many mapping from vendors to warehouses/parts through schedule records.

4) Why the correct answer is correct
- The statement “Each vendor can supply many parts to any number of warehouses, but need not supply any parts.” directly matches the 0..* optional cardinality on the vendor side and the many relationships allowed by the supply-schedule associative entity.

5) Why other options are incorrect
- “Each warehouse can be supplied with any number of parts...and could be supplied with no parts.” The diagram’s connector to WAREHOUSE does not show optional 0 on the warehouse end, so the claim about warehouses being allowed to have no parts is not supported.
- “Each part must be supplied by exactly one vendor to any number of warehouses.” The diagram does not show a strict “exactly one vendor” constraint for PART; PART is connected through the associative entity allowing multiple associations.
- “VENDOR is not allowed.” Incorrect: VENDOR appears and participates in the relationship; it is allowed (optionally).

6) Conclusion
The correct business rule is: “Each vendor can supply many parts to any number of warehouses, but need not supply any parts.” This matches the provided answer.

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