text: 
  CREATE OR REPLACE FUNCTION c_post_has_trans(
      post_id BIGINT,
      lang_id BIGINT
  )
  
  RETURNS BOOL
  
  LANGUAGE SQL
  VOLATILE
  RETURNS NULL ON NULL INPUT
  PARALLEL UNSAFE
  
  AS $$
  
  SELECT EXISTS(
      SELECT 1
      FROM t_post_translations
      WHERE tpt_post = post_id
          AND tpt_lang = lang_id
      LIMIT 1
  )
  
  $$;
  