Quincey Koziol <koziol@xxxxxxxxxxxxx> writes:
> Hi Mike,
>
>> This question came up today at the NASA briefing, when we were talking
>> about the netCDF 4 project. There was a weak but immediate and negative
>> reaction to using time as a proxy for creation order. The reason given was
>> that many applications would want to use the creation time as an attribute,
>> but that the times used would not necessarily give the same ordering as
>> creation time because different times might be relative to different time
>> zones. I have a feeling there were other cases, given the reaction people
>> had.
>>
>> Of course this could only happen if people were allowed to change the
>> "creation time." And one could also argue that creation time is a
>> different attribute -- it's the time the link was created, not the time the
>> data was collected. But I have a feeling this would just lead to confusion.
>>
>> So at best, I think there is concern that this could led to confusion. I
>> tend to agree.
>
> Ok, I think we've heard enough customer push-back on this that we ought to
> provide both options and allow people to choose which they'd like. Here's a
> list of the fields that I'm planning on storing on storing for each link:
> - Name (indexable, must be unique, modifiable)
> - Creation time (indexable, may be non-unique, modifiable)
> - Creation order (indexable, unique, monotonicly increasing,
> non-modifiable)
> - Character set (i.e. ASCII, UTF-8, etc.) (non-indexable?, non-unique,
> modifiable)
> - Object address/link target (for hard/soft links) (non-indexable, may be
> non-unique (for multiple links to same object), modifiable?)
>
> Applications can determine which of the three indexable fields they'd like
> to have an index maintained for with a group creation property. They will
> choose an index for iteration, etc. with a group access property.
>
> Quincey
Thanks Quincey!
I think that will work better for netCDF-4.
Ed
--
Ed Hartnett -- ed@xxxxxxxxxxxxxxxx
