[mapserver-users] Impact of InValid Geometry on PostGIS queries

[Ben Madin]

G'day all,

I have a roads shapefile which I imported in PostGIS, planning to  
merge several different countries data eventually. It is producing a  
layer on the map, and labels etc.

However, the data isn't all good - in fact, about 10% is bad :

es=# select IsValid(the_geom), count(gid) from gis_roads group by  
IsValid(the_geom);

  isvalid | count
----------+-------
               |  4128
       t       | 39670
(2 rows)

My question then is :

should I ?

a) leave it - it won't do any harm, but probably won't be rendered,
b) remove it - it may be incorrectly rendered, or waste processor time  
on data that is unuseable,
c) fix it by hand (lazy git!)
d) fix it automatically, using super program I wasn't aware of.  
(called?)

actually, I don't have the time or budget for option c, and I suspect  
option d does not exist!

cheers

Ben



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Ben Madin
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