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Performing Database health checks

Performing Database health checks, when there is an issue reported by Application users. 1. Check the Database details 2. Monitor the consumption of resources 3. Check the Alert Log 4. Check Listener log 5. Check Filesystem space Usage 6. Generate AWR Report 7. Generate ADDM Report 8. Finding Locks,Blocker Session and Waiting sessions in a oracle database 9. Check for alerts in OEM 1. Check the Database details :- ============================= set pages 9999 lines 300 col OPEN_MODE for a10 col HOST_NAME for a30 select name DB_NAME,HOST_NAME,DATABASE_ROLE,OPEN_MODE,version DB_VERSION,LOGINS,to_char(STARTUP_TIME,'DD-MON-YYYY HH24:MI:SS') "DB UP TIME" from v$database,gv$instance; For RAC: ------- set pages 9999 lines 300 col OPEN_MODE for a10 col HOST_NAME for a30 select INST_ID,INSTANCE_NAME, name DB_NAME,HOST_NAME,DATABASE_ROLE,OPEN_MODE,version DB_VERSION,LOGINS,to_char(STARTUP_TIME,'DD-MON-YYYY HH24:MI:SS') "DB UP TIME" from...

Oracle DBA - Questions and Answers

What is difference between oracle SID and Oracle service name? Oracle SID is the unique name that uniquely identifies your instance/database where as the service name is the TNS alias can be same or different as SID. What are the steps to install oracle on Linux system? List two kernel parameter that effect oracle installation? Initially set up disks and kernel parameters, then create oracle user and DBA group, and finally run installer to start the installation process. The SHMMAX & SHMMNI two kernel parameter required to set before installation process. What are bind variables? With bind variable in SQL, oracle can cache queries in a single time in the SQL cache area. This avoids a hard parse each time, which saves on various locking and latching resource we use to check object existence and so on. What is the difference between data block/extent/segment? A data block is the smallest unit of logical storage for a database object. As objects grow they take chunks ...