Here some lines explain about the header of a block. Normally we know have seen block corrupt but what if when the first block of a datafile containing the datafile header becomes corrupt. The header of a block contains information like the type of segment the block belongs to and the SCN of the last […]
Monthly Archives: September 2017
Recover corrupted data blocks using DBVERIFY
As we know that SYSTEM – stores the data dictionary. Being an Oracle DBA we all know the importance of SYSTEM tablespace. In these below lines, we can have actual technical knowledge about system’s information. SYSTEM – a tablespace that is always used to store SYSTEM data that includes data about tables, indexes, sequences, and other objects – this metadata […]
Recover sparse corrupted data blocks one several datafiles
Being an Oracle DBA we all are known about data block. Here this line explains the technical definition of data block A data block is the smallest unit of storage in an Oracle database. Every database has a default block size (specified when the database is created), although blocks in different tablespaces may have different […]
Recover contiguous corrupted data blocks
Being a DBA we all have good knowledge on feature of its database. As we know that Oracle has introduced a new feature in 11g which can be used to get assistance in case of loss or corruption of datafiles, redo log files or controlfiles. This tool is called data recovery advisor and is accessible from […]
Recover a never backed up tablespace after losing its datafile
In this post, we are going to learn steps which are use recover a never backed up tablespace after losing its datafile and even the current controlfile after the autobackup feature completes its job. This crash involves the lost of the “never backed up” tablespace and of the current controlfile. Let’s start with an example. Our […]
Recover a never backed up tablespace after losing its datafile
This post is about the steps which are used to recover a never backed up tablespace after losing its datafile and even the current controlfile but before the autobackup feature completes its job. All the required information is still available and written in your archived or online redo log. So the solution of the first question […]
Restore the spfile while using the flash recovery area and not the recovery catalog
We all are aware of spfile and pfile in Oracle. Oracle requires an initialization file to define the attributes and characteristics of the starting instance and the connecting sessions there of. We are aware of the Initialization parameter file (also referred as init.ora file or PFILE). This file holds the setup parameters that define the attribute […]
Restore from a loss of all current control files to a non default location
This post about to restore from a loss of all current control files to a non-default location using autobackup. One of the many features included in RMAN is the ability to automatically backup your control file. It is very important for (some) recovery purposes to ensure you have a recent copy of your control file, especially if […]
Restore from a loss of all current control files to the default location
Recovery of the most crucial element in Oracle database plays an important role. with the help of show parameter control_files we can find the default location of controlfile in our database. Being an Oracle DBA we must know that why do need oracle controlfile in any oracle. There are some main points which remind us to […]
Retrieve the DATABASE IDENTIFIER from datafiles or online logs
This article is about the steps which require recovery when we retrieve the DATABASE IDENTIFIER dumping it from datafiles or online and archived redo logs . DBID stands for database identifier, which is a unique identifier for each Oracle database running. It is found in control files as well as datafile header. If the database is open […]