lag DG查看当前数据文件头最小的scn号：
select min(to_char(CHECKPOINT_CHANGE#)) from v$datafile_header ff;

增备脚本：
rman target / << EOF
run
{
allocate channel c1 type disk;
allocate channel c2 type disk;
allocate channel c3 type disk;
allocate channel c4 type disk;
allocate channel c5 type disk;
allocate channel c6 type disk;
allocate channel c7 type disk;
allocate channel c8 type disk;
allocate channel c9 type disk;
allocate channel c10 type disk;
allocate channel c11 type disk;
allocate channel c12 type disk;
allocate channel c13 type disk;
allocate channel c14 type disk;
allocate channel c15 type disk;
allocate channel c16 type disk;
BACKUP as compressed backupset INCREMENTAL FROM SCN 15844047884184 DATABASE FORMAT '/paic/tmp/nasshare/gmpor/hdq404/incr/standby__%d_%s_%p_%t' tag 'FORSTANDBY' ;
backup current controlfile for standby format '/paic/tmp/nasshare/gmpor/hdq404/incr/stdctl.ctl'; 
release channel c1;
release channel c2;
release channel c3;
release channel c4;
release channel c5;
release channel c6;
release channel c7;
release channel c8;
release channel c9;
release channel c10;
release channel c11;
release channel c12;
release channel c13;
release channel c14;
release channel c15;
release channel c16;
}
EOF