ruby - Rails - PostGIS + postgis_adapter Geometry Problem -

i use postgis_adapter alongside postgresql 9.0.4, postgis 1.5.2 , rails 3.1.0 on ruby 1.9.2. described in the postgis_adapter readme, tried perform

model.create(:geom => point.from_x_y(10,20)) 

postgres responds with

error: parse error - invalid geometry hint: must specify valid ogc wkt geometry type such point, linestring or polygon 

the created georuby object looks this:

#<georuby::simplefeatures::point:0x0000010420a620 @srid=4326, @with_z=false, @with_m=false, @y=20, @x=10, @z=0.0, @m=0.0> 

hopefully got idea.

executive summary: may work if change to:

model.create(:the_name_of_your_geo_column => point.from_x_y(10,20))

longer version, high probability of ruby howlers: i've barely written word of rb saw 1 many great projects week continue in state of ignorance. working through error messages in irb (starting 0 in language familiar postgis):

activerecord::base.establish_connection(:adapter=>'postgresql',:database=>'moveable')  pt = tablepoint.new(:data => "hello!",:geom => point.from_x_y(1,2)) nameerror: uninitialized constant point 

so, require 'postgis_adapter', then:

pgerror: error:  relation "table_points" not exist 

this must awesome naming convention in activerecord i've heard about. create table called table_points because don't know database model/sync methods are.

moveable=> create table table_points(data text, geo_something geometry); 

notice here used geometry rather geography because first instinct problem modeling methods in database adapter layer created point types. not @ all, actually. again in irb,

pt = tablepoint.new(:geom => point.from_x_y(1,2)) activerecord::unknownattributeerror: unknown attribute: geom     

no attribute named geom? see happen, again in psql:

moveable=> alter table table_points add column geom geometry; alter table 

then:

irb(main):014:0> pt = tablepoint.new(:geom => point.from_x_y(10,20)) => #<tablepoint data: nil, geo_something: nil, geom: #<georuby::simplefeatures::point:0x1022555f0 @y=20, @with_m=false, @x=10, @m=0.0, @with_z=false, @z=0.0, @srid=-1>> irb(main):015:0> pt.save => true 

unbelievable! if did:

pt = tablepoint.new(:data => 'is possible?', :geom => point.from_x_y(38,121), :geo_something => point.from_x_y(37,120)) => #<tablepoint data: "is possible?", geo_something: #<georuby::simplefeatures::point:0x102041098 @y=120, @with_m=false, @x=37, @m=0.0, @with_z=false, @z=0.0, @srid=-1>, geom: #<georuby::simplefeatures::point:0x1020410c0 @y=121, @with_m=false, @x=38, @m=0.0, @with_z=false, @z=0.0, @srid=-1>> irb(main):023:0> pt.save => true 

even more unbelievable!

moveable=> select * table_points;   data  |  geo_something  |  geom   --------+-----------------+--------         |                 | 0101000000000         | 010100000000000 |          | 010100000000000 |  ...ble? | 00005e400000000 | 010000405e40 (4 rows) 

i hesitate post answer because of fundamental lack of familiarity ruby above works (mindbendingly, me), , may able adapt case.