G'day all,
I hope no one minds this, but I have to deal with some changes to my
data, and thought it might be a good opportunity to ask the basic
questions I've been dwelling on for some time.
Having just received a new set of the spatial data I am working with
(shapefiles of administrative regions), I am unsurprised to find that
about 15 districts have gone (been amalgamated), some new ones
appeared, and indeed one entire province removed!
My intention was to add two columns to my gis data table -
geom_start_validity & geom_end_validity, and revise my queries (which
normally are analysing / displaying movement information) to choose
the appropriate geometry depending on the date range of the query.
Is the approach sound? (Is this a reasonable idea? Am I completely off
track here? Will this make my table difficult to index? Should I find
all the polygons which are the same and delete the duplicates,
extending the validity dates?)
(The interface which relates to the entry of movements would also be
amended to deliver a different set of provinces and districts
depending on the date of the movements. How I deal with movements that
occur over the transition is beyond me so far!)
cheers
Ben
--
Ben Madin
REMOTE INFORMATION
t : +61 8 9192 5455
f : +61 8 9192 5535
m : 0448 887 220
Broome WA 6725
[email protected]
Out here, it pays to
know...
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