ruby on rails - Foreign key does not exist when deleting dependent records -

i have 2 models. first one:

class keyword < activerecord::base    has_many :words, dependent: :delete_all  end 

the second:

class word < activerecord::base  end 

my migrations:

class keywords < activerecord::migration   def change     create_table :keywords |t|       t.string :name, null: false, unique: true       t.string :description, null: false        t.string :keys, null: false       t.timestamps null: false     end   end end 

and words:

class words < activerecord::migration   def change     create_table :words |t|       t.belongs_to :keyword       t.string :name, null: false       t.timestamps null: false     end   end end 

when i'm trying delete keywords instance rails throws out following exception:

pg::undefinedcolumn: error: column words.keyword_id not exist line 1: delete "words" "words"."keyword_id" = $1 ^ : delete "words" "words"."keyword_id" = $1 

so question is, why rails created keyword_id reference table instead of using keywords_id? , how fix it.

the code in repository different migration code posted. in repo have:

t.belongs_to :keywords 

change to:

t.belongs_to :keyword 

as posted in question , recreate database.