Before you restore the data file from the RMAN backup, verify whether the missing data file physically exists at the OS level. Also confirm that the Oracle software owner has the appropriate read and write privileges on the missing data file and directory.
We also recommend querying the data dictionary for more information. The V$DATAFILE_HEADER view derives its information from the data file headers and reports in the ERROR and RECOVER columns any potential problems.For example, a YES or null value in the RECOVER column indicates there is a problem:
: I want to display the maxsize for a tablespace data file.
Maxsize is the total of maxsize of datafiles in that particular tablespace which is the total of Megabytes allocated to the datafiles.
alter database datafile 'file1' size 10G autoextend on maxsize 32G;
alter database datafile 'file2' size 15G autoextend on maxsize 32G;
Normal tablespace scripts including the one on this site is having total of size of datafiles (that is 10g + 15g = 25g).
I am looking for script which will use maxbytes of datafiles (that is 32g + 32g = 64g).