Purge unused fields

[GoogleCodeExporter]

In issue 133, Aaron asks: "Is it possible to start off by purging all of the 
fields that have never been used?"

Original issue reported on code.google.com by cpw...@gmail.com on 26 Feb 2013 at 12:05

[GoogleCodeExporter]

May include
* tree_damage
* tree_damage_details

Original comment by cpw...@gmail.com on 26 Feb 2013 at 12:09

[GoogleCodeExporter]

May include
* tree_diameter

Original comment by cpw...@gmail.com on 26 Feb 2013 at 12:13

[GoogleCodeExporter]

We should be able to do a simple query and count non-blank or non-NULL cells, 
correct?
...or would that require creation of a dozen more indices?  Oh, the joys of 
NOSQL... database optimization: 1. Optimization? We don't need no stinking 
optimization! 2. You'd better get it right the first time, because if you try 
for it later, you will explode your DB in the attempt, thus rendering any 
resulting optimization futile.

Original comment by v...@aarontitus.net on 26 Feb 2013 at 2:16

[GoogleCodeExporter]

I have a vague uneasy feeling that in very short order the database will become 
completely beyond the control of any human, making fixes and migration 
impossible.
Call me old-fashioned, but I like understanding my own database. I don't want 
to be forced to rely on SkyNet to fix my database for me.

Oh, Google... into thy hands I commend my digital soul... ;-)

Original comment by v...@aarontitus.net on 26 Feb 2013 at 2:27