ruby on rails - SQLite3::SQLException: unrecognized token: ":": -

i'm having trouble running pg_search. think it's set correctly, reason when trying run search, comes up:

sqlite3::sqlexception: unrecognized token: ":": select "courses".*, ((ts_rank((to_tsvector('simple', coalesce("courses"."title"::text, ''))), (to_tsquery('simple', ''' ' || 'finance' || ' ''')), 0))) pg_search_rank "courses"  (((to_tsvector('simple', coalesce("courses"."title"::text, ''))) @@ (to_tsquery('simple', ''' ' || 'finance' || ' ''')))) order pg_search_rank desc, "courses"."id" asc 

course model:

include pgsearch scope :by_course_title, lambda { |ttl|   _by_course_title(ttl) if ttl.present? } pg_search_scope :_by_course_title, against: :title 

search controller:

def index     @course = course.by_course_title(params[:fname]) end 

in html:

<% @course.each |courses| %>     <div><%= courses %></div> <% end %> 

is possible caused .each? if keep <%= @course %>, page loads , shows:

#<activerecord::relation:0x....> 

am supposed convert resulting array before passing .each function?

you have postgresql specific library (pgsearch) , you're using sqlite3 database. pick 1 or other, not both.

the casting operator :: in coalesce("courses"."title"::text, '') valid postgresql only. sqlite can leave out casting (the ::text part), mentioned before, won't pgsearch work correctly unless switch on postgresql database.