> In your language, can you query:
> How many fruit colors are there?
> Which fruit color(s) is/are the most liked?
> How many veggies are there that nobody likes?
An updated example with min, max, sum, avg and count functions.
(; Create qty 28, 30, 35)
(new '25 'quantity)
(new '30 'quantity)
(new '35 'quantity)
(; Create a verb named age)
(new 'age 'verb)
(; Create a person named john whose age is 25)
(new 'john 'person)
(create john age 25)
(; Create a person named mary whose age is 30)
(new 'mary 'person)
(create mary age 30)
(; Create a person named bob whose age is 35)
(new 'bob 'person)
(create bob age 35)
(; Create a person named sue whose age is unknown)
(new 'sue 'person)
(; Count persons)
(; Returns qty instance named 4)
(count (select person instance *))
(; Count persons with age)
(; Returns qty instance named 3)
(count (and (select person instance *)
(select * age)))
(; Get minimum age of persons)
(; Returns qty instance named 25)
(min (select (select person instance *) age *))
(; Get maximum age of persons)
(; Returns qty instance named 35)
(max (select (select person instance *) age *))
(; Get sum of persons age)
(; Returns qty instance named 90)
(sum (select (select person instance *) age *))
(; Get average of persons age)
(; Returns qty instance named 30)
(avg (select (select person instance *) age *))
For details, see www.dbfordummies.com/example/ex045.asp
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