ORACLE DBA

SCN and Checkpoint in Oracle What is SCN and why it is used? What happens if the SCN in datafile header is not matching with the Control file? The system change number (SCN) is Oracle's clock, every time we commit the clock increments. The SCN just marks a consistent point in time in the database. The checkpoint SCN in datafile headers are updated after checkpoint. The SCN is incremented whenever a transaction commits. Suppose i do update in one table which is stored in two different datafiles it will update all datafiles header & write information in control file after commit. Before opening the database SMON will check the control file & datafile headers for the same SCN. If the SCN in datafile header is not matching with the Control file that means datafile need recovery. How to find Current SCN? SQL> select dbms_flashback.get_system_change_number from dual; VER. Oracle 9i SQL> select to_char(current_scn) from v$database;     ...

How to find out the Oracle port numbers oracle@YesBolisetty.MY:/home/oracle [MYDB] >  cat $ORACLE_HOME/ install/portlist.ini Enterprise Manager Console HTTP Port (MYDB) = 1158 Enterprise Manager Agent Port (MYDB) = 3938

http://www.orafaq.com/wiki/Category:Backup_and_Recovery

SCOPE : RMAN automatic Tablespace Point-In-Time Recovery ( TSPITR) enables you to quickly recover one or more tablespaces in an Oracle database to an earlier time, without affecting the state of the rest of the tablespaces and other objects in the database.  Prior to 11.2 version the TSPITR had a restriction of not being able to recover the dropped tablespace. From 11.2 this limitation no longer exists. We can recover the dropped tablespace using TSPITR. The below example is an attempt to show the steps and functioning of TSPITR to recover a dropped tablespace. Example: 1) Create a tablespace. SQL> create tablespace users datafile 'D:\DATABASES\ORA11G\users01.dbf' size 10m reuse; SQL> select tablespace_name from dba_tablespaces; TABLESPACE_NAME ------------------------------ SYSTEM SYSAUX UNDOTBS1 TEMP USERS 2) Create a user and create a table in the new tablespace. SQL> create user tiger identified by tiger; SQL> grant dba to tiger; SQL> conn ...

                                                                                                          ఆ చల్లని సముద్ర గర్భం దాచిన బడబానలమెంతో  ఆ నల్లని ఆకాశంలో కానరాని భాస్కరులెందరో  ||ఆ చల్లని|| భూగోళం పుట్టుక కోసం రాలిన సుర గోళాలెన్నో  ఈ మానవ రూపం కోసం జరిగిన పరిణామాలెన్నో ఒక రాజుని గెలిపించుటలో ఒరిగిన నర కంఠములెన్నో కుల మతాల సుడిగుండాలకు బలియైన పవిత్రులెందరో  ||ఆ చల్లని|| మానవ కళ్యాణం కోసం పణమెత్తిన రక్తము ఎంతో  రణరక్కసి కరాళ నృత్యం రాచిన పసి ప్రాణాలెన్నో కడుపు కోతతో అల్లాడిన కన్నులలో విషాదమెంతో  భూస్వాముల  దౌర్జన్యాలకు  ధనవంతుల దుర్మార్గాలకు  దగ్ధమైన బతుకులు ఎన్నో  ||ఆ చల్లని|| అన్నార్తులు అనాథలుండని ఆ నవయుగమదెంత దూరం  కరువంటూ కాటకమంటూ కనిపించని కా...

The purpose of this document is to provide a working example and show you how to Install and setup GoldenGate Replication between two Oracle databases on Unix platforms This guide uses examples and assumes details that you may need to modify for your environment. Contents ------------------------ Verify Database Configuration Requirements Install & Setup GoldenGate Software and Administrator user Configure the Manager process Prepare Objects for Capture Configure Extract for Change Capture and Extract Pump Configure Initial Data Load Configure Delivery Test Replication Verify Database Configuration Requirements ============================== Ensure that the following environment variables are set. ORACLE_HOME ORACLE_SID TNS_ADMIN Verify archive log mode is setup correctly As SYS user execute: archive log list If the source database is not in archivelog mode, enable it using below steps: alter system set log_archive_dest='LOCATION=USE_DB_RECOVERY_FILE_DEST' scope=both ...