quest sql optimizer for oracle keygen software keys

Quest Sql Optimizer For Oracle Software Keys How To Read These

Janis webcasts are always packed with valuable information, and this one didnt disappoint as she imparted her expertise in SQL query tuning on the Oracle platform.

If its unclear why or even if the query results are being used, then maybe that query doesnt need to run at all and you can immediately see some performance gains by disabling it.

Start your tuning efforts with the queries taking the most time.

You can use V Views to see real-time performance and session information.

Although this information does not persist, Janis demonstrated a query that polls the V Views and creates a table of the data on sessions, wait events, blocking session IDs, etc.

If you automate this query and poll every second, you can begin to see trends over time and can focus on the queries that take the longest time.

If you are an Oracle Enterprise Edition user and own the Tuning and Diagnostic Packs, you can access the view called VActiveSession History, which holds an hour of session data.

She tends to look at buffer gets to determine whether shes making progress in tuning.

Tuning the query that requires the most buffer gets will often have a positive trickle-down effect on other queries.

An explain plan is an estimate of what the query will do and can be wrong for many reasons.

A cached plan will show you an actual plan that the Optimizer used.

Quest Sql Optimizer For Oracle Software Keys How To Read These

Knowing how to read these plans gives you insight into what the Optimizer is doing.

Because the Optimizer continues to evolve with Oracle versions, you should become familiar with how it treats execution plans with each new release.

Look at statistics gathering are the statistics current, or if theyre not, do they hurt the choices the Optimizer is making.

Be sure you understand the order of columns and column selectivity in the index.

In short, you study Joins and Filtering predicates to filter the data earlier in the query rather than later.

This part of the presentation really tied together how it makes sense to take a methodical approach to Oracle SQL query tuning.

When it feels overwhelming, Foglight makes the process much more manageable.

Quest Sql Optimizer For Oracle Keygen Software Keys