???????????????????????????????????? ????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????? ?????!???????????????????????????????????????????????????????????????????????????????????????? ????????????????????????? ??????????????????????????????????????????????????   ????????

Returns the particular Model of your collation object as it is actually at present installed during the running system. If this is different from the value in pg_collation.collversion, then objects according to the collation may possibly must be rebuilt. See also Change COLLATION.????????????????????????????????????????? ??? pg168 ?????????????????