ruby on rails - Thinking sphinx - how to index type of STI model -

is there way index type of sti model (a polymorphic model's association in ruby) , not itself? example, have model comment:

class comment < activerecord::base   belongs_to :commenter, polymorphic: true   ... end 

is possible sphinx index commenters , not comments?

to specific, instead of sphinx.conf looking like

source comment_core_0 {   ...   sql_query = select sql_no_cache comments.id * 60 + 2 id,      'comment' sphinx_internal_class_name,      comments.id sphinx_internal_id,      'comment' sphinx_internal_class     ... } 

i want sphinx.conf like:

source comment_core_0 {   ...   sql_query = select sql_no_cache comments.commenter_id * 60 + 2 id,      commenter_type sphinx_internal_class_name,      comments.commenter_id sphinx_internal_id,      commenter_type sphinx_internal_class     ... } 

thanks

i'm afraid isn't possible thinking sphinx - built expect index maps single model. also, in situation you've described (if make work in sphinx directly, rather ts), end duplicate records if commenter has more 1 comment.

you'd better have indices each commenter type , search across of these indices @ once.