MAX_STRING_SIZE Parameter In Oracle 12c

This parameter was introduced in Oracle 12c. MAX_STRING_SIZE controls the maximum size of string size in Oracle database. Either we can set it to STANDARD or.EXTENDED The default value is STANDARD MAX_STRING_SIZE = STANDARD means the maximum size of strings is 4000 bytes for VARCHAR2 and NVARCHAR2 MAX_STRING_SIZE = EXTENDED means maximum size can be upto 32767 byte . We can change the value of MAX_STRING_SIZE from STANDARD to EXTENDED. But not from EXTENDED to STANDARD. With MAX_STRING_SIZE set to STANDARD , […]

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Switchback to the original location of the previously corrupted/damaged datafile

In this article, we are going to have look on How to switch back to the original location of the previously corrupted/damaged/lost/canceled datafile. RMAN> report schema; using target database control file instead of recovery catalog Report of database schema for database with db_unique_name ORCL List of Permanent Datafiles =========================== File Size(MB) Tablespace RB segs Datafile Name […]

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Recover a corrupted/damaged NON-SYSTEM datafile switching to an image copy when database in ARCHIVELOG mode

This article is about recovery of corrupted/damaged/lost/canceled NONSYSTEM datafile switching to an image copy when database in ARCHIVELOG mode. We must have an image copy of my datafiles: The following command is use to take copy. [oracle@localhost orcl]$ rman target / RMAN> backup as copy database; Starting backup at 19-07-2012 07:45:31 using channel ORA_DISK_1 channel ORA_DISK_1: […]

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Oracle Licenses

Despite reams of legalese and countless blog/forum posts, basic Oracle RDBMS licensing still remains a mystery to many. While I won’t even begin to discuss components like Oracle Apps, hopefully this post may help you attain a basic understanding of Oracle, what you can license, and what it costs. Editions The first and most important […]

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Restore the spfile while using the FRA & not using Recovery Catalog

Today we are going to learn about recovery with rman for loss of spfile. As we know that RMAN can be used either with or without a recovery catalog. A recovery catalog is a schema stored in a database that tracks backups and stores scripts for use in RMAN backup and recovery situations. Generally, a skillful DBA […]

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FAR SYNC in Oracle 12C Database

Oracle introduced a new feature for DataGuard called Far Sync. This configuration is design to support synchronous redo transport between primary and standby database which are far apart. In usual configuration synchronous redo transport between data centre in Europe and US is possible but inefficient from the primary database performance perspective. Every commit has to be written […]

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PDBs Backup (How to identify which PDBs a backup set belong to)

Introduction:- In this article, we are going to have look on PDBs backup.  Normally we have learnt about a different kind of backup available in  Oracle. In cloud computing, we have backups in PDBs. In RMAN we have a script to know about the backup history. Now we can get the information of PDB(backup).  n large scale industries have […]

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Migrating Oracle ASM Disk Groups without OCR or Voting Files

To migrate Oracle ASM disk groups without Oracle Cluster Registry (OCR) or voting files to Oracle ASMFD: Log in as the Oracle Grid Infrastructure owner on any node to run the commands in this procedure. List the existing disk groups: $ $ORACLE_HOME/bin/asmcmd lsdg List the associated disks: $ $ORACLE_HOME/bin/asmcmd lsdsk -G diskgroup Check if Oracle […]

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Oracle ASMLIB v/s Oracle ASM Filter Driver (ASMFD)

Oracle ASM Filter Driver (Oracle ASMFD) is installed with an Oracle Grid Infrastructure installation. If you have an existing Oracle ASM library driver (Oracle ASMLIB) configuration, then depending on whether you want to use Oracle ASMLIB or Oracle ASMFD, consider the following scenarios: If you use Oracle ASMLIB to manage your Oracle ASM devices and […]

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Tablespace growth in Oracle

— Find Tablespace growth size in number of days. set feed off set pages 1000 lines 180 column “tablespace_name” heading “Tablespace | Name” format a20 select to_char (sp.begin_interval_time,’dd-mm-yyyy’) days, ts.tsname, max(round((tsu.tablespace_size* dt.block_size )/(1024*1024),2) ) cur_size_mb, max(round((tsu.tablespace_usedsize* dt.block_size )/(1024*1024),2)) usedsize_mb from dba_hist_tbspc_space_usage tsu, dba_hist_tablespace_stat ts, dba_hist_snapshot sp, dba_tablespaces dt where tsu.tablespace_id= ts.ts# and tsu.snap_id = sp.snap_id and […]

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