I do the development with MySQL, and there is no errors, but in Heroku with PostgreSQL i'm having a bad time.
This is the code where it complains:
joins( [ :invoice, { :invoice => :project } ] ).group("projects.name").order("value DESC").sum("receipts.value")
It gives me this message : "ActiveRecord::StatementInvalid (PGError: ERROR: column "receipts.value" must appear in the GROUP BY clause or be used in an aggregate function"
Do you know how can I resolve this issue?
Thank you in advance.