One Cause of ORA-01092

I saw the following error in a job which had just recreated the control file of a test database after cloning:

SQL>   2    3    4    5    6    7    8    9   10   11   12   13   14   15   16   17   18   19   20   21   22   23   24   25   26   27   28   29   30   31   3
2   33   34   35   36   37   38   39   40   41   42   43   44   45   46   47   48   49   50   51   52   53   (more...)

Recursion in Oracle 12

Oracle 12 has a new parameter called PGA_AGGREGATE_LIMIT:

SQL> conn system/manager
Connected.
SQL> l
  1  select value from v$parameter
  2* where name = 'pga_aggregate_limit'
SQL> /
 
VALUE
--------------------
2147483648
 
SQL>

You cannot set it below 2 gigabytes:

SQL> alter system
  2  set pga_aggregate_limit = 1g;
alter system
*
ERROR at line 1:
ORA-02097: parameter cannot be modified because
specified value is invalid
ORA-00093: pga_aggregate_limit must be between 2048M

RECOVER DATABASE TEST

I logged into an Oracle 12.1 database and ran the ALTER DATABASE BEGIN BACKUP command. This told Oracle I was about to start a hot backup:

C:UsersAdministrator>sqlplus / as sysdba
 
SQL*Plus: Release 12.1.0.1.0 Production on Thu Mar 26 10:08:51 2015
 
Copyright (c) 1982, 2013, Oracle.  All rights reserved.
 
Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.1.0 - 64bit Production
With the (more...)

A Simple Example With V$BACKUP

I tested this in an Oracle 12.1 database. The V$BACKUP view tells you if a datafile is in hot backup mode. I started off with none of the datafiles in hot backup mode so they were all shown as NOT ACTIVE:

SQL> select file#, status from v$backup
  2  /
 
     FILE# STATUS
---------- ------------------
         1 NOT ACTIVE
         2 NOT ACTIVE
         3 NOT ACTIVE
         5 NOT ACTIVE
    (more...)

Re-Creating Datafiles When Backups Are Unavailable

I found an old copy of the Oracle 9i User-Managed Backup and Recovery Guide and read the following:
 
If a datafile is damaged and no backup of the file is available, then you can still recover the datafile if:
 
·         All archived log files written after the creation of the original datafile are available
·         The control file contains the name of the damaged file (that is, the control file is (more...)

DBMS_STATS Causes ORA-00600 [15851]

Uncategorized
| Apr 3, 2013
I noticed this in an Oracle 11.2.0.1.0 database. DBMS_STATS failed with an ORA-00600 and the first argument was [15851]. On investigation, it seemed to have something to do with the fact that the table had a function based index:
 
SQL> SELECT COUNT(*) FROM DBA_INDEXES