The emergency radio network records equipment inspections using Fig. 1. Each radio has a serial number. Inspectors complete several checks during one inspec...
Question 1 Report
The emergency radio network records equipment inspections using Fig. 1. Each radio has a serial number. Inspectors complete several checks during one inspection, and the database must record the result of every check without repeating the inspection date for each item.
(a) State the relationship between Inspection and CheckResult. [1]
(b) Give two fields that could form a composite key in CheckResult. [2]
(c) State one field that should be stored in Inspection. [1]
(d) Give one advantage of this design over placing Check1, Check2 and Check3 in Inspection. [1]
(e) State a suitable data type for a pass or fail result. [1]
Answer Details
This design separates an inspection from its individual check results. It avoids storing a fixed set of repeating Check fields.
- (a) One Inspection can have several CheckResult records, so the relationship is one-to-many. [1]
- (b) A suitable composite key is InspectID and CheckCode. Together they identify one particular check in one inspection. [2]
- (c) Inspection could store an inspection date, inspector ID, or SerialNo. [1]
- (d) This design allows any number of checks to be recorded, without repeating fields, and makes new checks easier to add. [1]
- (e) A pass/fail result has two states, so a suitable data type is Boolean. [1]
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