update ktz_xy set ktz_xy.dmlvl = (select tdfldm1.dmlvl from tdfldm1 where ktz_xy.dldm=tdfldm1.dldm )
选择ktz_xy表中凡是dldm 与tdfldm1表的dldm 相同的记录,将其值ktz_xy.dmlvl 修改为tdfldm1.dmlvl 的值
update ktz_xy set ktz_xy.dmlvl = (select tdfldm1.dmlvl from tdfldm1 where ktz_xy.dldm=tdfldm1.dldm )
选择ktz_xy表中凡是dldm 与tdfldm1表的dldm 相同的记录,将其值ktz_xy.dmlvl 修改为tdfldm1.dmlvl 的值