=centercr
@ []QUERY Q 3.2.1: Find employment periods in the Toy department for persons that
have worked there for at least 8 years.
ANSWER: ``{ [1/1/82 - now]}''
CATEGORY: (None, Element, Union) / (Duration, Element, Explicit) /(=,
Constant)
=centercr
@ []QUERY Q 3.2.2: Find the starting times of managers which managed a department
for at least 5 years.
ANSWER: ``{ 1/1/82}''
CATEGORY: (None, Element, Derived) / (Duration, Element, Explicit) /(=,
Constant)
=centercr
@ []QUERY Q 3.2.3: Find the rehiring dates of employees with a gap in employment
that exceeds 1 month.
ANSWER: ``{ 4/1/87}''
CATEGORY: (None, Element, Union) / (Duration, Element, Explicit) /(=,
Constant)
=centercr
@ []QUERY Q 3.2.4: Find the times when persons possessed skills that they lost and
regained more than 1 year later.
ANSWER: ``{ [1/1/82 - 5/1/82], [6/1/84 - 5/31/88]}''
CATEGORY: (None, Element, Derived) / (Duration, Element, Explicit) /(=,
Constant)
=centercr
@ []QUERY Q 3.2.5: Find budget periods that exceed 2 years.
ANSWER: ``{ [1/1/87 - now], [4/1/87 - now]}''
CATEGORY: (None, Element, Derived) / (Duration, Element, Explicit) /(=,
Constant)
=centercr
@ []QUERY Q 3.2.6: When did no one's salary change for at least six months?
ANSWER: ``06/01/82–07/31/84,'' ``08/01/84–01/31/ 85,''
``02/01/85–08/31/86,'' ``09/01/86–now.''
CATEGORY: (None, Interval, Derived) / (Duration, Interval, Explicit)
(temporal aggregate) /