Top Frequency Histograms

The maximum number of bins in an Oracle frequency histogram is 254 and as we all know there are almost always more than 254 bins for frequency distributions. Oracle 12c has introduced a new concept, to help deal with the problem, the Top Frequency Histogram.

The post Top Frequency Histograms appeared first on Stelios Charalambides.

Three Great Things You Didn’t Know About SQLT

SQLT is an amazing tool with a host of user friendly features. This post covers three I've found particularly useful; how to use SQLT on a test database where it isn't installed, how to get rid of histograms and how, when your system is large, you can get the information (more...)

Oracle Database Statistics Gathering

What do you know about Oracle Database statistics gathering? What would you like to know? There is a section in the Database Performance Tuning Guide, but how many people take the time to read it? And, once you know what the various procedures are and what they do, how do (more...)

Severity One Killer

When there's a major change in the performance of your database the culprit can usually be found by looking at any changes made around the time that performance degraded, but what if nothing has changed? What do you do then? There are lots of options, but only one that will (more...)

XTRSBY – Tuning Oracle Data Guard

If you're reading this, you probably love SQLT and want to learn more about it, but sometimes, a SQLT Xtract isn't the best tool for the job. Here's an example, tuning Data guard. Using the right tool always makes the job a little easier.

The post XTRSBY – Tuning Oracle (more...)

Why Doesn’t My Hint Work?

Have you ever used a hint as a quick fix and ended up spending far too much time on it, wondering why doesn't my hint work?  Here's what might be going on.

The post Why Doesn’t My Hint Work? appeared first on Stelios Charalambides.

What is SQLT?

There's nothing more annoying than having to struggle to do something because you don't have the right tools. That's why I love my swiss army knife and why when working for Oracle, I love SQLT. What is SQLT? Read on and find out.

The post What is SQLT? appeared first (more...)

Tuning Oracle SQL – Just Another Blog?

Find out why you should read and subscribe to this blog rather than the hundreds of others on Oracle SQL Tuning. Got a tuning problem you can't solve? Send in your SQLT report!

The post Tuning Oracle SQL – Just Another Blog? appeared first on Stelios Charalambides.