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Flashback query is a powerful and useful feature introduced in Oracle 9i, and enhanced greatly in Oracle 10g, that can help us recover data, lost or corrupted, due to human error. One big advantages of using flashback over point-in-time recovery is that for the latter not only transactions from the time of error to the current time would be lost but also the system will be unavailable for the duration of the recovery. For flashback query, on the other hand, there will be no down time needed and repair or recovery is less labor and time intensive than what it used to be in earlier versions of Oracle. With the new features like Recycle Bin, Flashback databases and Flashback Drop in Oracle 10g, the flashback capability introduced in 9i has been improved tremendously now turning a small feature into a powerful tool in the new Oracle releases. Type of flashback recovery: Flashback Database (We can revert database at a past time) Flashback Drop (Reverses the effects of a DRO

Some feature is not enabled in oracle database standard edition, as a result we can not use flashback feature in Oracle Database if you are use in standard edition of oracle. Following Error Message show in Oracle 10g standard edition SQL> alter database flashback on; alter database flashback on * ERROR at line 1: ORA-00439: feature not enabled: Flashback Database Version of Oracle   SQL> SELECT * FROM V$VERSION; BANNER ---------------------------------------------------------------- Oracle Database 10g Release 10.2.0.1.0 - Production PL/SQL Release 10.2.0.1.0 - Production CORE    10.2.0.1.0      Production TNS for 32-bit Windows: Version 10.2.0.1.0 - Production NLSRTL Version 10.2.0.1.0 - Production Features are available in standard edition   SQL> SELECT Parameter,Value FROM V$OPTION Where Value = 'TRUE'; PARAMETER                                                        VALUE                                                            -----------------

There are two approaches to take Backup of control file in Oracle: Backing it up in a binary format Backing it up in a human readable format Syntax: alter database backup controlfile to ['filename' | trace] This command comes in two versions. One backs up the control file in a binary format while the other backs it up in a human readable form. It is required if the database is running in archive log mode and a structural change was made to the database. Backing it up in a binary format: You can generate a binary image of the Control File SQL Code: alter database backup controlfile                to '/some/arbitrary/path'; alter database backup controlfile                to '/some/arbitrary/path' reuse; Backing it up in a human readable format: You generate a text file script which will re-generate a Control File when run as a SQL script. The file name will be something like ‘ ora_<some numbers>.trc’ SQL Code: alter databa

A cancel-based recovery is a type of user-managed incomplete recovery that is performed by specifying the UNTIL CANCEL clause with the RECOVER command (a SQL*Plus command that is used to recover a database). The UNTIL CANCEL clause specifies that the recovery process will continue until the user manually cancels the recovery process issuing the CANCEL command. In a cancel-based incomplete recovery, the recovery process proceeds by prompting the user with the suggested archived redo log files’ names. The recovery process stops when the user specifies CANCEL instead of specifying an archived redo log file’s name. If the user does not specify CANCEL, the recovery process automatically stops when all the archived redo log files have been applied to the database. A cancel-based recovery is usually performed when the requirement is to recover up to a particular archived redo log file. For example, if one of the archived redo log files required for the complete recovery is

C:\Documents and Settings\Administrator>sqlplus "/as sysdba" SQL*Plus: Release 10.2.0.1.0 - Production on Mon Jun 28 10:25:39 2010 Copyright (c) 1982, 2005, Oracle.  All rights reserved. Connected to: Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production With the Partitioning, OLAP and Data Mining options SQL> select * from tab; select * from tab               * ERROR at line 1: ORA-01219: database not open : queries allowed on fixed tables/views only   Shutdown the database first SQL> shutdown immediate; ORA-01109: database not open Database dismounted. ORACLE instance shut down. Start the database SQL> startup ORACLE instance started. Total System Global Area  599785472 bytes Fixed Size                  1250356 bytes Variable Size             180358092 bytes Database Buffers          411041792 bytes Redo Buffers                7135232 bytes Database mounted. ORA-16038: log 2 sequence# 135 cannot be archived ORA-19809: limit exceeded fo

Cause: The archiver process received an error while trying to archive a redo log. If the problem is not resolved soon, the database will stop executing transactions. The most likely cause of this message is the destination device is out of space to store the redo log file. Action: Check archiver trace file for a detailed description of the problem. Also verify that the device specified in the initialization parameter ARCHIVE_LOG_DEST is set up properly for archiving.alter database flashback on There is two possible way to solution. 1. without increasing DB_RECOVERY_FILE_DEST_SIZE . 2. by increasing DB_RECOVERY_FILE_DEST_SIZE . Without increasing DB_RECOVERY_FILE_DEST_SIZE. 1. Check whether the database is in archive log mode and automatic archiving is enabled. SQL> archive log list; Database log mode              Archive Mode Automatic archival             Enabled Archive destination            USE_DB_RECOVERY_FILE_DEST Oldest online log sequence     29 Next l

SQL Server 2017 Version Build KB Release Date CU-9 14.0.3030.27 KB4341265 July 2018 CU-8 14.0.3029.16 KB4338363 June 2018 CU-7 14.0.3026.27 KB4229789 May 2018 CU-6 14.0.3025.34 KB4101464 April 2018 CU-5 14.0.3023.8 KB4092643 March 2018 CU-4 14.0.3022.28 KB4056498 February 2018 CU-3 14.0.3015.40 KB4052987 January 2018 CU-2 14.0.3008.27 KB4052574 November 2017 CU-1 14.0.3006.16 KB3164674 October 2017 RTM 14.0.1000.169 October 2017 SQL Server 2016 Version Build KB Release Date SP2 CU-2 13.0.5153.0 KB4340355 July 2018 SP2 CU-1 13.0.5149.0 KB4135048 May 2018 Service Pack 2 13.0.5026.0 KB4052908 April 2018 SP1 CU-8 13.0.4474.0 KB4077064 March 2018 SP1 CU-7 13.0.4466.4 KB4057119 January 2018 SP1 CU-6 13.0.4457.0 KB4037354 November 2017 SP1 CU-5 13.0.4451.0