SPARSE FILES on unix databases
when you create a tempfile in Oracle that run in unix, the tempfile is created as "Sparse File" ie.
tempfile doesn´t fill all space that it seem to have.
When you resize a tempfile from database, it does not grow in operating system until you fill file space in database
SQL> alter database tempfile '/u8515/oradata/PRODBD/temp01.dbf' resize 3G;
In s.o:
bash # du -h /u8515/oradata/PRODBD/temp01.dbf;ls -lh /u8515/oradata/PRODBD/temp01.dbf| awk '{print " " $5" "$9}'
2.0G /u8515/oradata/PRODBD/temp01.dbf
3.0G /u8515/oradata/PRODBD/temp01.dbf
Sparse files are good for random access but when you run out of room in your device
you had to take into account that df -h doesn´t show real free space...a lot of times
i have expanded a datafile filling up the file system and causing problems when tempfile needs his real database space.
would be possible that create tempfiles as sparse files, it be an optional parameter when you created a tempfile in Oracle Rdbms?