[Data-modeling] Upcoming Schema Changes

[Robert Cook]

I've been working on loading the current CIA World Factbook, and like  
you I'm convinced that there will ultimately be a lot of utility for  
properties containing time series values.  The real question is what  
to do when an API user who wants to see a single value -- the most  
recent one -- without a complicated query?   These two use cases (time  
series vs. the canonical up-to-date value) are a little at odds, and  
it seems like there are at least a couple of possible solutions:

1. Create a second time-series property for population.  This would be  
a denormalization, where the most recent value is also copied into the  
current population property.

2. Add functionality to MQL to ask for the "most recent" value in a  
time series if it's queried as a single value.  Of course, MQL would  
have to know about dated integers and dated floating point values,  
along with any other dated CVT.  There would have to be some  
additional indicator on the property at the schema level that  
indicated it was a time series so that MQL would know when to affect  
this behavior.

#1 could be done right now, whereas something like #2 would probably  
be non trivial.  There may be better ideas.

Do you see a serious problem adding  "historical population" on  
Statistical Region to hold your time-series data?

R

On Feb 11, 2008, at 9:47 PM, Jeff Thompson wrote:

> Bryan Cheung wrote:
>> The type company currently has properties which have an expected type
>> of money value. However, these are monetary values associated with a
>> given point in time. As such, we have modeled a type dated money  
>> value
>> to represent a money value at a specific date. The expected values of
>> the monetary properties of type company should be updated to use the
>> type dated money value.
>>
>>     * /business/company/net_income
>>     * /business/company/operating_income
>>     * /business/company/revenue
>
> (This is my cue to beat an old horse.)  Will you only allow a single  
> Dated
> Money Value to show the net_income for 2008.  That is, when we know  
> the net_income
> for 2009, will you *add* this information to the data for 2008 to  
> keep the
> running history, or will you delete the information for 2008?
>
> I ask because the population property for San Francisco has a Dated  
> Integer for 2006
> (the most recent census). I add added the census population for  
> 2000, but someone
> deleted it, probably assuming it was a mistake.
>
> - Jeff
>
>
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