Curate a OFE group ID

[akrherz]

@dejames52 and @edulukin have been patiently waiting for me to do some analysis of what they called an uniqueid to classify our DEP OFEs into comparable groups. I'd rather not call this value uniqueid as that implies something it is not. I'll instead call it a groupid and it will be represented by an underscore seperated string of values in the form <slopeclass>_<kwfactclass>_<tillagecode>_<genlandusecode> where

slopeclass is

Bulk slope %	class
0 <= x <= 2	1
2 < x <= 4	2
4 < x <= 6	3
6 < x <= 12	4
12 < x	5

kwfactclass is

kwfact	class
0 < x <= 0.28	1
0.28 < x <= 0.32	2
0.32 < x	3

tillagecode and genlandusecode are verbatim.

TODO

• create database storage
• assign these at import time
• update current database entries with these

[akrherz]

The SQL run to update the current entries

update flowpath_ofes o
SET groupid = case when bulk_slope <= 0.02 then 1 when bulk_slope <= 0.04 then 2 when bulk_slope <= 0.06 then 3 when bulk_slope <= 0.12 then 4 else 5 end
||'_'|| case when kwfact <= 0.28 then 1 when kwfact <= 0.32 then 2 else 3 end 
||'_'|| substr(f.management, 1, 1) ||'_'|| l.label
from gssurgo g, fields f, general_landuse l where o.gssurgo_id = g.id
and f.field_id = o.field_id and f.genlu = l.id ;