text: ALTER TABLE t_poscat
      ADD COLUMN associd bigint;
  
  UPDATE t_poscat
  SET associd = t_cmassocdef.associd
  FROM t_poscat tp
  LEFT JOIN t_cmassocdef ON t_cmassocdef.companyid = tp.companyid;
  
  ALTER TABLE t_poscat
      DROP COLUMN companyid;
  