Oracle Invisible Indexes and Index Usability
:
Many of the decisions to create an index in production are not always rooted in explain plan analysis or from looking at application code. What often happens is hundreds of indexes cluttering up the databases. Two mechanisms within Oracle could help you clean up these unused or performance hogging indexes.
Modeling Oracle Time
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It is often difficult to zero in on where to spend time tuning an Oracle database. From a very high level, Oracle Time Model can provide direction and offer feedback for tuning.
Hidden treasures in Oracle's STATSPACK utility
:
STATSPACK is still very much a viable option for monitoring and diagnosing database performance. Even though it seems as if AWR and ADDM have voted to send STATSPACK to Exile Island, treasures and rewards can still be found, but it's up to you to find them and make the most of what's available.
Unleashing DBMS_PROFILER
:
The DBMS_PROFILER package has been around since at least Oracle8i days, yet it seems to get short shrift in many of the tuning books and online discussion forums. Learn how easy it is to implement and perhaps you'll add this built-in to your tuning arsenal.
Measuring Disk I/O-Oracle’s ORION Tool
:
Oracle’s ORION workload tool enables architects to effectively
develop a workload that can mimic and stress a storage array in the same manner
as planned applications with an Oracle backend database.
Measuring Disk I/O—A Vendor View
:
Learn how to compare the workload of a database with the actual mechanical capabilities of individual disks.
Measuring Disk I/O
:
Oracle has a variety of I/O types that
ultimately need to be mapped, sampled, and related to storage.
This article looks at extracting various I/O statistics so that you can monitor
and determine just how well your disks are doing.
More on Using Tools for Tracing
:
There is more than one approach or tool to use in a “tuning opportunity.”
Part two of this article covers Tracing and TKPROF.
Saving Time by Reusing Storage
:
While truncating a table to remove data is faster than deleting the same data, there are subtle differences that when taken into account, can help improve the overall performance of a job or process. Read on to learn the advantages and disadvantages of each.
Tuning an Oracle Procedure
:
Join JP Vijaykumar as he tunes a procedure that is running for eight hours,
bringing the run time of the procedure down to three hours.
Getting Inside the Optimizer – Part 2
:
You don’t have to accept what Oracle (or a third party tool) does in terms of an execution plan recommendation. Learn how to distinguish between which to accept and reject.
Getting Inside the Optimizer
:
If you had a tool that could display different execution plans,
wouldn’t it be useful to see what those plans are, and even better, pick up
some ideas on how to improve the efficiency of you SQL code? Toad’s SQL
Optimizer tool can do just that.
Getting
a Handle on Indexes : Performance is the number one reason why indexes
are needed. However, there are situations where indexes are not needed. Read on
to learn when and where to index.
Oracle 10gR2 Adaptive Thresholds, Part 2: Implementation
: This article – the last in this series – demonstrates how to
implement adaptive thresholds and use their metrics to effectively detect
significant performance threshold violations while tuning out the
"noise" from false positives.
Oracle
10gR2 Adaptive Thresholds, Part 1: Overview : This article – the first
in this series – discusses how adaptive thresholds are designed to improve the
detection of threshold violations, including the ability to discern a false
positive from a true warning.
Reviewing
Views : Views are extremely useful for DBAs, developers, and users
alike, but are you getting all you can out of what views have to offer?
Oracle
Performance Tuning – Part 2 : There are several relatively easy steps
you can take to improve performance. From the user's perspective, one of the
most frequently used interfaces with a database involves SQL statements, so
getting a handle on them is a good place to start, in terms of being able to
see an immediate improvement.
Oracle
Performance Tuning – Part 1 : Oracle's Tuning Methodology changed when
Oracle 9i was released. The approach went from top-down in 8i to that of
following principles in 9i/10g. Neither methodology is absolute as each has its
advantages and disadvantages. Read on to learn more.
Clustering
for Indexes : Indexes hold the key for speed when accessing data. To
ensure that you are getting to the data as fast as possible you should check to
make sure the clustering is suitable for the query type.
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