List,

Thanks for the help recently for my two questions regarding buffers. Here
are the oringinal questions and a selection of the answers received:

Q 1 - I have 2 tables, one with burst records (point) and the other with
pipes (line). I have created a buffer around the points (20m) so that I can
select those records that only have 2 or more pipes intersecting the buffer.
Problem is, I can't get this to work. I've tried every possible combination
of SQL Select that I can think of. Anybody out there got any ideas?

Answer:
select from the menu bar >>Table>>>update column

in the top most dialog box select your buffered layer
in the third box down select your lines layer
in the box marked VALUE, click and select count
now click on the join button and make sure that the tables are joined
graphically so that the buffered table INTERSECTS the lines table
click ok
click ok
you should now have a temporary column added to your bursts table,
this column has a count of all pipes intersecting each buffer zone, 

do a nice easy SQL for all bursts where the temp column is > 2

Thanks Russel and Yannick)


Q 2 - I have buffers that I created around points. What I wish to do is
place the point ID onto the associated buffer. Update column works fine for
most of them, but where I have 2 or more point/buffers in the same place,
only one of the point IDs is attached to all of the buffers. Is there any
way around this?

Answers:

open the new table mypoints

You need to open the mapbasic window (options>>>>open mapbasic window)
and cut'n'paste the following into the window, hilite it and press
return

set coordsys table mypoints
set distance units "m"
update mypoints set obj =
createcircle(centroidx(obj),centroidy(obj),20)

To get buffers of different sizes change the value '20' in the above
text
To get buffers in different units  change the value "m" in th eabove
text

(The text above creates circles of 20m radius from points)

(Thanks to Russel, Tim, Glen and jchgis)


Once again, thanks list for your help - what would I do without you?


Tom
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