When the last time a datafile was used

Question

Hello.
This is from Solaris box, running Oracle 8.1.7.4.0.
There are two datafiles, actually three, that were created for three tablespaces. These in total take up more than 3G on the server and space is at a premium.
I suspect that these files can be removed but I need to understand when the last time they were used and if it is safe to remove them.
Each of these files was created as 800M files and each has 799.99M remaining.
Thank you for any advice.
DA

Answer 1

it doeasn't help when you use ls -l, because the system checkpoint will upate all the datafiles(except the readonly ones)
SQL> create tablespace myts datafile '/tmp/myts.dbf' size 50M;
Tablespace created.
SQL> create table mytable1 (col1 date, col2 number) tablespace myts;
Table created.
SQL> !ls -ltr /tmp/*.dbf
-rw-r----- 1 oracle oinstall 52436992 Apr 18 09:22 /tmp/myts.dbf
SQL> alter system switch logfile;
System altered.
SQL> !ls -ltr /tmp/*.dbf
-rw-r----- 1 oracle oinstall 52436992 Apr 18 09:22 /tmp/myts.dbf
SQL> alter system checkpoint;
System altered.
SQL> !ls -ltr /tmp/*.dbf
-rw-r----- 1 oracle oinstall 52436992 Apr 18 09:24 /tmp/myts.dbf
if you want to drop the tablespace, just simply run the following command. it should be successful if your TS is empty:
SQL> drop tablespace myts;
drop tablespace myts
ERROR at line 1:
ORA-01549: tablespace not empty, use INCLUDING CONTENTS option
SQL> select segment_name,segment_type from dba_segments where tablespace_name='MYTS';
SEGMENT_NAME
SEGMENT_TYPE
MYTABLE1
TABLE
SQL> drop table MYTABLE1 purge;
Table dropped.
SQL> drop tablespace myts;
Tablespace dropped.
Or you can run the following command directly if you confirm to drop everything in this TS:
drop tablespace myts INCLUDING CONTENTS ;
HTH
Scott