CONFIGURE BACKUP OPTIMIZATION ON;
CONFIGURE DEFAULT DEVICE TYPE TO DISK;
CONFIGURE CONTROLFILE AUTOBACKUP ON;
CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO '/u01/orabackup/backupsets/ora10g-%F.ctl';
CONFIGURE DEVICE TYPE DISK PARALLELISM 1 BACKUP TYPE TO BACKUPSET;
CONFIGURE DATAFILE BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # default
CONFIGURE ARCHIVELOG BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # default
CONFIGURE MAXSETSIZE TO UNLIMITED; # default
CONFIGURE ENCRYPTION FOR DATABASE OFF; # default
CONFIGURE ENCRYPTION ALGORITHM 'AES128'; # default
CONFIGURE ARCHIVELOG DELETION POLICY TO NONE;
CONFIGURE SNAPSHOT CONTROLFILE NAME TO '/u01/app/oracle/product/10.2.0/db_1/dbs/snapcf_ora10g.f'; # default
可以看到，刚才MAXPIECESIZE的值在show all中已经不存在了，也就是对备份片没有限制了
再次进行备份，可以通过脚本运行，也可以单独执行下面的备份语句：
RMAN> backup as compressed backupset database format '$RMAN_BACKUPSETS/$ORACLE_SID-%I_%T_%t_%s.db' tag 'db_bak' plus archivelog format '$RMAN_BACKUPSETS/$ORACLE_SID-%I_%T_%t_%s.arc' not backed up 1 times delete all input tag 'arc_bak';
[oracle@ora10g backupsets]$ . ../scripts/backup_full.sh
RMAN> RMAN> RMAN> RMAN> RMAN> RMAN> RMAN> RMAN> RMAN> RMAN> 2> 3> RMAN> RMAN> RMAN> RMAN>
[oracle@ora10g backupsets]$? ls -lrth ../backupsets/
total 553M
-rw-r----- 1 oracle oinstall 9.8M Dec 24 14:24 ora10g-4175411955_20141224_867162246_380.arc
-rw-r----- 1 oracle oinstall 1.7M Dec 24 14:24 ora10g-4175411955_20141224_867162255_381.arc
-rw-r----- 1 oracle oinstall 439K Dec 24 14:24 ora10g-4175411955_20141224_867162257_382.arc
-rw-r----- 1 oracle oinstall 747K Dec 24 14:33 ora10g-4175411955_20141224_867162820_384.arc
-rw-r----- 1 oracle oinstall 170M Dec 24 14:36 ora10g-4175411955_20141224_867162823_385.db
-rw-r----- 1 oracle oinstall 491K Dec 24 14:36 ora10g-4175411955_20141224_867162990_386.arc
-rw-r----- 1 oracle oinstall 7.3M Dec 24 14:36 ora10g-c-4175411955-20141224-00.ctl
-rw-r----- 1 oracle oinstall? 30K Dec 24 14:39 ora10g-4175411955_20141224_867163193_388.arc
-rw-r----- 1 oracle oinstall 7.4M Dec 24 15:03 ora10g-4175411955_20141224_867164604_390_1.arc
-rw-r----- 1 oracle oinstall? 99M Dec 24 15:05 ora10g-4175411955_20141224_867164614_391_1.db
-rw-r----- 1 oracle oinstall? 73M Dec 24 15:06 ora10g-4175411955_20141224_867164614_391_2.db
-rw-r----- 1 oracle oinstall? 22K Dec 24 15:06 ora10g-4175411955_20141224_867164776_392_1.arc
-rw-r----- 1 oracle oinstall 7.3M Dec 24 15:06 ora10g-c-4175411955-20141224-01.ctl
-rw-r----- 1 oracle oinstall 457K Dec 24 15:25 ora10g-4175411955_20141224_867165923_394.arc
-rw-r----- 1 oracle oinstall 170M Dec 24 15:28 ora10g-4175411955_20141224_867165927_395.db
-rw-r----- 1 oracle oinstall? 20K Dec 24 15:28 ora10g-4175411955_20141224_867166094_396.arc
-rw-r----- 1 oracle oinstall 7.3M Dec 24 15:28 ora10g-c-4175411955-20141224-02.ctl
[oracle@ora10g backupsets]$
第3次执行备份脚本生成的备份集没有分片（因为去掉了%p参数），同时也去掉了MAXPIECESIZE的限制
总结
如果才RMAN参数中配置了MAXIECESIZE的值为一个给定的具体值时，那么再FORMAT中必须叫上%p的通配符，否则一旦备份片超过设定的上限值后，就无法生成后续备份片，导致备份失败。因此通常情况下，建议配置MAXPIECESIZE参数，并且在FORMAT中加上%U通配符，它包含了%u（自动计算出的唯一8位编号）,%p（备份片号）,%c（备份片拷贝数，1-256）。