update X_YBYPJBBIAOZHUN a
set ybypbianma=(select b.ybypguojiabianma from X_YBYPduiying210508 b where b.ybypjiubianma=a.ybypid)
where exists (select 1
from X_YBYPduiying210508 b where b.ybypjiubianma=a.ybypid
);
ybypguojiabianma字段中有重复值。我想应该在问题在这。