ActiveRecord::StatementInvalid: PG::UndefinedTable: ERROR: relation “people” does not exist

Question

I'm trying to create a new rails project. Here is my schema:

ActiveRecord::Schema.define(version: 2020_07_22_184104) do

  # These are extensions that must be enabled in order to support this database
  enable_extension "plpgsql"

  create_table "houses", force: :cascade do |t|
    t.string "address"
  end

  create_table "persons", force: :cascade do |t|
    t.string "name"
    t.integer "house_id"
  end

end

Now, when I try to create a Person instance in rails console, I get this error:

ActiveRecord::StatementInvalid: PG::UndefinedTable: ERROR:  relation "people" does not exist
LINE 8:                WHERE a.attrelid = '"people"'::regclass
                                          ^
:               SELECT a.attname, format_type(a.atttypid, a.atttypmod),
                     pg_get_expr(d.adbin, d.adrelid), a.attnotnull, a.atttypid, a.atttypmod,
                     c.collname, col_description(a.attrelid, a.attnum) AS comment
                FROM pg_attribute a
                LEFT JOIN pg_attrdef d ON a.attrelid = d.adrelid AND a.attnum = d.adnum
                LEFT JOIN pg_type t ON a.atttypid = t.oid
                LEFT JOIN pg_collation c ON a.attcollation = c.oid AND a.attcollation <> t.typcollation
               WHERE a.attrelid = '"people"'::regclass
                 AND a.attnum > 0 AND NOT a.attisdropped
               ORDER BY a.attnum

from C:/Ruby26-x64/lib/ruby/gems/2.6.0/gems/activerecord-5.2.4.3/lib/active_record/connection_adapters/postgresql/database_statements.rb:63:in `exec'
Caused by PG::UndefinedTable: ERROR:  relation "people" does not exist
LINE 8:                WHERE a.attrelid = '"people"'::regclass

The House model works fine. My development and test databases are also being newly created, so I don't think there's any issue with the tables. Why is this error referring to "people" relation when my table name is persons?

Answer 1

Plural form of word "person" is "people" that is why Rails tries to call a table with this name. Change the name of your table or set the table name in your model.

class Person < ApplicationRecord
  self.table_name = 'persons'
end

See naming conventions .