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How to check Oracle SGA component size

A very simple query to display SGA components in Oracle database SELECT * FROM v$sgainfo;

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How to analyze wait events in Oracle

User below query to get the top wait classes in Oracle database Select wait_class, sum(time_waited), sum(time_waited)/sum(total_waits) Sum_Waits From v$system_wait_class Group by wait_class Order by 3 desc; From the above query, supply each wait class into below query to get the top wait events...

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How to set DISPLAY variable in Linux

Whenever you want to invoke graphical interface in Linux, You must know how to set DISPLAY variable in order to open the GUI. Linux by default does not allow you to open any GUI (Linux Oracle Installer) until you enable the GUI display. Enabling DISPLAY Variable Use below command to enable Linux...

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Crontab error - permission denied

When you try to schedule backups under corntab as Oracle user, you might encounter crontab permission error [[email protected] ~]$ crontab -l cron/oracle: Permission denied Resolving Crontab Permission Error The error is because of permission issues on /usr/bin/crontab file. Login as root user...

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How to check FRA location utilization in Oracle

Flash Recovery Area must be monitored regularly. Sometimes FRA runs our of space and a DBA must be able to gather FRA space utilization. It is very important to monitor space usage in the fast recovery area to ensure that it is large enough to contain backups and other recovery-related...

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How to check last modified table in Oracle

As a DBA, application team sometimes might ask you to provide details of last modified table in oracle. The table modification can be insert, update or delete. Below queries get details of last or latest modified table in oracle database. Run the queries depending upon the database version. Last...

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How to check check single table size in oracle

Once you run the query, it will ask your table name. Enter the table name in the format of owner.tablename. Eg - scott.emp select segment_name,segment_type, sum(bytes/1024/1024/1024) GB from dba_segments where segment_name='&Your_Table_Name' group by segment_name,segment_type;

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How to check database PITR after refresh

Database refresh is common task for a DBA. But after every database refresh, you must check the PITR date and time. This should be checked before you issue OPEN RESETLOGS command. Query to Check PITR – Issue it before OPEN RESETLOGS select distinct to_char(checkpoint_time,'dd/mm/yyyy...

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How ot check archive generation in Oracle

The below query gives results of archive generation in oracle database. Use below query to find the archive space requirements and you can use it to estimate the archive destination size perfectly well. Query to check archive generation in oracle SELECT A.*,...

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How to disable firewall in Linux 7

Disabling firewall in Linux 5/7 versions is little bit different than Linux 7. Sometimes you need to disable firewall in Linux 7 version as part of Database installation pre-requisites. This article will help you to find the status of firewall and then enable / disable it. Firewall Status The...

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