Re: Does Codd's view of a relational database differ from that ofDate&Darwin?[M.Gittens]

On 21 Jun 2005 05:56:54 -0700, "vc" <boston103_at_hotmail.com> wrote:

>Hi,
>
>Alexandr Savinov wrote:
>>
>>... But the FDM query
>>
>> for each s in employee
>> print(getName(s), getAge(s),
>> getName(getBuilding(getDepartment(s))))
>>
>> also does not have any indication about order in which elements will be
>> processed and there is no iterator in it
>
>That is correct but insufficient for the fragment to be interpreted in
>a declarative way. What possible meaning can you ascribe to 'for each'
>as a function ? 'map' as in map(sqrt, [1,4,9]) evaluating to [1,2,3] ?
>What does 'for each' evaluate to ? What kind of function is 'print' ?
>When you ask yourself these questions, the only possible
>interpretation would be imperative, no matter the original collection
>traversal order. The same reasoning of course applies to 'return' and
>such.

"employee" is a variable with an state and such code has "side-effects". It is completely imperative.

Regards Received on Tue Jun 21 2005 - 09:18:31 CDT