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<DIV><FONT face=Arial size=2>Last week I ran into a problem where I created a
tiled layer of tiger line roads, and when I tried to view the whole area of my
map (which is basically the NE portion of the US from pennsylvania up to Maine)
it caused the server to use up all of its memory and start shutting down
processes. It was pointed out to me, that even though I was
only displaying one particular road type which by itself wouldn't be a lot of
data, mapserver still had to inspect every road in the shapefile to match it to
my expression and therefore was very inefficient.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>So, if I'm understanding correctly, a better way to
do it would be to break the shapefiles down into individual road types and have
a separate layer for each type... for example I could have an interstate
shapefile, a state highway shapefile, a major roads shapefile, and a minor roads
shapefile and make a separate layer for each of them. </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>How can I pre-process those shapefiles to separate
them into their components? I don't necessarily have to tile them, I
was only doing that so that I could combine all of the shapefiles into one (the
tiger shapefiles are per-county so there are a ton of them). If
there is another way to combine those into one I could do that as
well. I just don't know how to break the tiger road shapefiles
into individual road types. </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Thanks for any suggestions and info,</FONT></DIV>
<DIV><FONT face=Arial size=2>Jeff</FONT></DIV>
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