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Kavramsal olarak, Active DataGuard teknolojisi şekilde gösterildiği gibi çalışır
Real-Time SQL Monitoring
With 11g version, the instantaneous monitoring and repor-
ting features provide many benefits as administrative.
With this feature, it is possible to observe instantly how much
and which source it used like CPU, IO. It brings a great deal
of practicality to can be seen on the screen in the same bind
variable values of SQL.
Adaptive Cursor ve SQL Plan Managament
Adaptive Cursor Sharing(ACS) provide cost based optimizer
(CBO) the opportunity to keep more than one plan for a
statement When creating execution plans.
To hold more than one execution plan means that SQL
statements which use bind variable is able to operate
different plans according to different bind variable values
which is leading a big performance gain..
With Oracle 11g the following tables has been developed to
follow and interpret whether cursor had been shared in bind
variable and 3 new views was added.
V$SQL_CS_STATISTICS,
V$SQL_CS_SELECTIVITY, V$SQL_CS_HISTOGRAM
All plans of running SQL statements are stored in the
database as SQL Plan Baseline. If it is generated a plan to
re-calculated for the related sql, it is not activated directly.
It is activated after verification of the performance is better
than ever. This is fabulous for DBAs who don't want to see
unexpected changes in the plan which can adversely affect
this performance.
At this new property that comes with 11g, it is possible to
test the changes in advance.
You can see the results before you make critical changes in
a production environment such as the database parameter
changes, OS and database updates, any changes to the
number of nodes (the most frequently asked questions by
the users of single node (What happens if the RAC?) In
this way, you would be plenty of time to solve problems
instead of searching for a solution under pressure and
encountering surprises on the morning of changes of your
critical systems.
Transaction Management
The historically examination
of how the data in database
changed has become more
available with 11g by using
Logminer and Flashback Data
Archive.
It was possible to follow the
exchange of data with respect
to time with the feature of 'Flash-
back query' at 10g. However,
usually the result could be
bought for a very minor slices
and limited by the size of the
UNDO file.
You are able to keep track of the exchange of data by
running Flashback Query at longer periods of time thanks
to taking the field independent for 11g flashback.
SQL Performance Analyzer ve
Real-Time SQL Monitoring
SQL Performance Analyzer
It is one of the most common questions on internet.
Oracle does not use an existing index? Why? Immediately
suggestions come, it is asked to be reduced from 100 of
optimizer_index_cost_adj default and a formula is given.
According to this formula, value is calculated as 10.
However, I wonder if I change the parameter will it be
beneficial to every sql?
After changing the database parameters or the version
of the optimizer it is now very easy to be able to test how
to behave the running sqls before changes with SQL Perfor-
mance Analyzer.
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