postgresql/contrib/earthdistance
Peter Eisentraut 74618e2b82 Another round of those unportable config/build changes :-/
* Add option to build with OpenSSL out of the box. Fix thusly exposed
  bit rot. Although it compiles now, getting this to do something
  useful is left as an exercise.

* Fix Kerberos options to defer checking for required libraries until
  all the other libraries are checked for.

* Change default odbcinst.ini and krb5.srvtab path to PREFIX/etc.

* Install work around for Autoconf's install-sh relative path anomaly.
  Get rid of old INSTL_*_OPTS variables, now that we don't need them
  anymore.

* Use `gunzip -c' instead of g?zcat. Reportedly broke on AIX.

* Look for only one of readline.h or readline/readline.h, not both.

* Make check for PS_STRINGS cacheable. Don't test for the header files
  separately.

* Disable fcntl(F_SETLK) test on Linux.

* Substitute the standard GCC warnings set into CFLAGS in configure,
  don't add it on in Makefile.global.

* Sweep through contrib tree to teach makefiles standard semantics.

... and in completely unrelated news:

* Make postmaster.opts arbitrary options-aware. I still think we need to
  save the environment as well.
2000-07-09 13:14:19 +00:00
..
earthdistance.c /contrib patch from Karel. 2000-06-15 18:55:34 +00:00
earthdistance.sql.in Add missing /contrib files to CVS. 2000-06-15 19:05:22 +00:00
Makefile Another round of those unportable config/build changes :-/ 2000-07-09 13:14:19 +00:00
README.earthdistance Add missing /contrib files 2000-06-19 14:02:16 +00:00

Date: Wed, 1 Apr 1998 15:19:32 -0600 (CST)
From: Hal Snyder <hal@vailsys.com>
To: vmehr@ctp.com
Subject: [QUESTIONS] Re: Spatial data, R-Trees

> From: Vivek Mehra <vmehr@ctp.com>
> Date: Wed, 1 Apr 1998 10:06:50 -0500

>  Am just starting out with PostgreSQL and would like to learn more about
> the spatial data handling ablilities of postgreSQL - in terms of using
> R-tree indexes, user defined types, operators and functions. 
> 
> Would you be able to suggest where I could find some code and SQL to
> look at to create these?

Here's the setup for adding an operator '<@>' to give distance in
statute miles between two points on the earth's surface. Coordinates
are in degrees. Points are taken as (longitude, latitude) and not vice
versa as longitude is closer to the intuitive idea of x-axis and
latitude to y-axis.

There's C source, Makefile for FreeBSD, and SQL for installing and
testing the function.

Let me know if anything looks fishy!

A note on testing C extensions - it seems not enough to drop a function
and re-create it - if I change a function, I have to stop and restart
the backend for the new version to be seen. I guess it would be too
messy to track which functions are added from a .so and do a dlclose
when the last one is dropped.