ruby on rails - N+1 detected on parent of parent model -

here model associations:

expense belongs_to supplier belongs_to concept  # example: "adsl connection , telephone july 2" > comcast > internet "water bill august 20" > pg&e > water 

i'm trying list of expenses, , show both company it's paid to, , concept belong to.

the bullet gem alerting me n+1 query , recommend include it:

n+1 query detected   supplier => [:payment_concept]   add finder: :include => [:payment_concept] 

and in controller, included supplier (for n+1) issue, when try include :payment_concept error it's not recognized symbol:

@expenses = expense.all(:include => [:supplier, :payment_concept])  # in view: .rows   - expense in @expenses     .item       p.date.lato= expense.date_made       p.supplier.lato= expense.supplier.name       p.payment_concept.lato= expense.supplier.payment_concept.name       p.payment_type.lato= expense.payment_type.name       p.account.lato= expense.account       p.price.lato= number_to_currency(expense.price)       .item-actions         = link_to '<i class="icon-remove"></i>'.html_safe, '#', class: 'small-button' 

understandable given expense has relationship supplier, , not directly it's concept.

any suggestions?

did try this?

 @expenses = expense.all(:include => [:supplier => :payment_concept]) 

edit:

for clarification, since concept belongs supplier (which belongs expenses), need use hash relationship in includes statement.