How long redo logs keep the transactions?

Question

I learn Oracle and decide to do an experiment. There was a table in the test database. I deleted the file that contained this table via OS. And then I added transactions to this table.
I did 'insert' several times, then 'commit', then 'alter system switch logfile' several times, 'alter system flush buffer_cache', 'alter system flush shared_pool' and nothing happened. I could add and take data from this table successfully. Alert log showed the error only when I shutdown the database.
SQL> shutdown immediate
ORA-01116: error in opening database file 13
ORA-01110: data file 13: '/oracle/oradata/test5/POSTEMPTEST2.dbf'
ORA-27041: unable to open file
Linux Error: 2: No such file or directory
Additional information: 3
I understand that transactions are put in the redo logs at first, and then are transferred to the datafile on disk. I thought that command 'ALTER SYSTEM CHECKPOINT' writes transactions from redo logs to datafile on disk, but I was wrong. How long redo logs keep transactions? Is there the way to push data from redo logs to datafile?
I use Oracle 10.2.0.1.0.

Answer 1

i believe this time you will see the error message during your SQLsWRONG!probably you did not read the complete post of mine before saying WRONG. You tell me, if data file containing a table is deleted at OS level (in *nix), and then you try to insert data in this table and want to retrieve the data from the table (If data is not in db cache or cache has been flushed), from where data will come? Or if you want to insert some data into this table for which new extent are required to be allocated, where it will be allocated? Will your SQLs succeed or will return some error? Either SQL should return you data (which is not possible as data file is no there to fetch the data), or SQL should fail with some error message.
I mimicked the situation on IBM AIX, following is the outcome.
Enter user-name: system/salman
Connected to:
Oracle Database 11g Release 11.1.0.7.0 - 64bit Production
SQL> create table test as select * from dba_tables;
Table created.
SQL> alter table test move tablespace users;
Table altered.
SQL> insert into test select * from dba_tables;
2500 rows created.
SQL> /
2500 rows created.
SQL> /
2500 rows created.
SQL> commit;
Commit complete.Now i deleted the users01.dbf file at OS level and then execute following INSERT
SQL> insert into test select * from test;
insert into test select * from test
ERROR at line 1:
ORA-01565: error in identifying file '/oracle/oradata/test/users01.dbf'
ORA-27037: unable to obtain file status
IBM AIX RISC System/6000 Error: 2: No such file or directory
Additional information: 3Salman