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How to increase memory_target in oracle

Before you can increase memory in oracle database, you must first understand four oracle memory parameters which govern the instance: SGA_TARGET and SGA_MAX_SIZE MEMORY_TARGET and MEMORY_MAX_TARGET SGA_TARGET and SGA_MAX_SIZE Important: If you set MEMORY_TARGET, they oracle will perform...

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How to find ASM disks mapping to physical disks

When you work in a RAC environment with a list of ASM disks, sometimes you might want to figure out which ASM disk is mapped to which physical device. Below is a simple script that will help you find out ASM disks that are mapped to Linux...

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How to find golden gate process memory usage

Each and every Golden Gate process takes approx 25 - 50 MB of memory or sometimes more depending upon the transactions. Here is one script which will help you find the total memory usage on source and target server. This script is written for linux #!/bin/bash ############################### #...

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How to check users, roles and privileges in Oracle

Query to check the granted roles to a user SELECT * FROM DBA_ROLE_PRIVS WHERE GRANTEE = '&USER'; Query to check privileges granted to a user SELECT * FROM DBA_TAB_PRIVS WHERE GRANTEE = 'USER'; Privileges granted to a role which is granted to a user SELECT * FROM DBA_TAB_PRIVS...

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How to check high resource intensive SQL in Oracle

Database performance is a major concern for a DBA. SQLs are the ones which needs proper DB management in order to execute well. At times the application team might tell you that the database is running slow. You can run below query to get the top 5 resource intensive SQL with SQL ID and then give...

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How to check execution plan of a query

First get the sql ID and then you can use below command to generate execution plan of a query in oracle SELECT * FROM table(DBMS_XPLAN.DISPLAY_CURSOR('2t3nwk8h97vph',0)); In case you have more IDs, use below command to supply sql id every time you run the query SELECT * FROM...

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How to backup archivelog for specific sequence RMAN

When you issue archive backup commands via RAMN, it will backup all the archive logs. Sometimes, you might need to backup only a particular archive log sequence. Below command will help you backup archive logs between specific sequence RMAN> BACKUP ARCHIVELOG FROM SEQUENCE 288 UNTIL SEQUENCE...

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How to check last CPU applied in Oracle

Generally if you have one single database install then checking the database inventory will give you the latest patch details. But! if we have multiple database in single oracle home then it might not give correct results. There might be a chance that one DB is applied with latest patches and...

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How to check biggest table in Oracle

As a DBA, you must keep an eye on the largest tables in the database. There are many things that get impacted with the largest objects like DB performance, growth, index rebuild etc. The below query gives you the top 10 largest tables in oracle database. Query to check top 10 largest tables in...

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How to check database backups via sqlplus

Checking Database backups are one of the main focus areas of a DBA. Time to time, DBA needs to check database backup status and see if its completed, failed, running etc. Also, DBA must be able to get the backup start time, end time and even the backup size for reference purpose. The below query...

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