Rails SQL Join two tables, One table has two columns with ids of other table, I need to get names of these ids -


this model associations:

class projectlinethreshold < activerecord::base   belongs_to :project_line   belongs_to :source, class_name: 'language'   belongs_to :target, class_name: 'language' end

projectlinethreshold table has these columns (:id, :source_id, :target_id, :score). need add names of languages source_id , target_id languages table.

i came statement :

thresholds = self.project_line_thresholds.joins(:source, :target)     .select('project_line_thresholds.id, project_line_thresholds.source_id, project_line_thresholds.target_id,       project_line_thresholds.score, languages.name source_name, languages.name target_name')

but same names target , source. proper join statement, or doing wrong?

the following query hit db once:

self.project_line_thresholds   .joins(:source, :target)   .includes(:source, :target)   .map {|plt| [plt.id, plt.source_id, plt.target_id, plt.score, source.name, target.name]}

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