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"If you were
plowing a field, which would you rather use? Two strong oxen or
1024 chickens?" - Seymour Cray (1925-1996), father of
supercomputing |
Read
first then play the video:
OEM012(VIDEO)-Obtaining
a SQL Statement Information
Obtaining a SQL statement
Information using OEM
Introduction
As a DBA, you are
responsible for obtaining SQL statement information for performance
tuning purposes. The following is a summary of your task:
Covers:
Selecting a target database
Obtaining the “Disk Reads
Per Execution” output
Obtaining the “Buffer
Gets Per Execution” output
Obtaining the “Execution”
output
Obtaining the “Disk Reads”
output
Obtaining the “Buffer
Gets” output
Obtaining the “Hit Ratio”
output
Hands-on
In this exercise you will
learn how to get information about SQL statements such as "Disk
Reads per Execution," "Buffer Gets Per Execution,"
"Executions," "Disk Reads," "Buffer
Gets," and etc from the "Top SQL" tool using the Oracle
Enterprise Management tools (OEM).
Expand the Databases item.
Select the DBS4RMAN database.
Go to the "Diagnostics Pack" tool and click on the "Top
SQL" icon.
Double click on the "DELETE from test" statement.
You can get:
"Disk Reads Per Execution,"
"Buffer Gets Per Execution,"
"Executions,"
"Disk Reads,"
"Buffer Gets,"
"Hit Ratio" and etc. As you can see there, is a lot of
information that can be viewed from this window.
We already have a job running in the background and the job is in the
loop.
Close the window.
Do the same for the other SQL statements.
Close the window.
Then, close the "Top SQL" window without saving the chart
option.
Suppress the expanded item.
We assume that you already know what the "Disk Reads,"
"Buffer Gets," and "Hit Ratio" are.
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