--up
  CREATE TABLE sample_voice_conversion_models (
    "sample_id" integer NOT NULL REFERENCES samples(id) ON DELETE CASCADE,
    "voice_conversion_model_id" integer NOT NULL REFERENCES voice_conversion_models(id) ON DELETE RESTRICT,
    "created_at" timestamp NOT NULL DEFAULT NOW(),
    "updated_at" timestamp NOT NULL DEFAULT NOW(),
    UNIQUE ("sample_id", "voice_conversion_model_id")
  );

  CREATE TRIGGER set_timestamp
  BEFORE UPDATE ON sample_voice_conversion_models FOR EACH ROW
  EXECUTE PROCEDURE update_updated_at_column();
--down
  DROP TABLE sample_voice_conversion_models;
