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Query Store: Your MSSQL Must-Have Feature (Part 2 of :”What a Shock! When You Suddenly Start Working With Other Databases..” series)

I have been working with Oracle database for so many years (as a DBA, as Application DBA, as a developer, as an architect, as a consultant, you name it), till suddenly, few years ago, I was practically forced to solve application performance issues happening in MSSQL for one of my customers who two-out-of-two of his SQL Server DBAs had left. A vacuum was created there, I was around, and I was requested to step into it and fill that vacuum. Well I do have many years of experience with tuning system and application, and it just happen that it needs to be done now on a different database than Oracle. No big deal, right? How different can that be?

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19 Great Things You Can Do With V$ACTIVE_SESSION_HISTORY (Part 1)

How many of you were using Oracle 9i, Oracle 8i, or even Oracle 7 back in the old days? And how many of you have tried to tune things with these versions? You have to admit life is so much easier this days when v$active_session_history is around (it has burst to our lives in Oracle 10g and was much improved in 11g).

Saying that, I still find myself surprised again and again to realize how unfamiliar v$active_session_history is among DBAs. And it shouldn’t be. Every now and then I bump into a DBA who is not using it, and it keep surprising me. I am saying to myself: “No way!” How come this is even possible when v$active_session_history has been around for so many years? Oracle 10g has been around since 2003 and working with v$active_session_history truly makes DBA’s life much more easier and simpler.

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What a Shock! When You Suddenly Start Working With Other Databases..(Part 1)

Back in the old days, many organizations were working with only one sort of database, and for many DBAs their knowledge-base was wrapped around this one specific database. This is hardly the case anymore. As data is massively growing, as data type are from all sorts, and as market needs are rapidly changing, organizations are now holding many kinds of databases, relational and non-relational, for all sort of needs. The days when you can stay as only one vendor DBA are long gone. It’s a natural change. The rapid reality will suck you into it even if you don’t do any proactive move toward it by yourself.

In case your massive DBA’s skills were evolved for many years with Oracle DB (like myself), and only then you started working with other databases, you have probably experienced some kind of a shock. I know it was a shock to me. And why was that?

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Yes, sometimes it is the database fault

Your database history is precious. Keeping it is crucial. Keep it as if you keep a valuable treasure.

And why is that? because it holds the normal and the abnormal behaviour of your database, and both or them are equally important.

It will save you, over and over again. That’s a guarantee. (more…)

Exadata Storage Index solving an endless update

The following simple update was running every evening, endlessly, on a production Exadata machine, Oracle version 11.2.0.3 (well, not truly endlessly, but for about an 30-60 minutes, which is considered to be quite endless in my standards…).  (more…)

No, It is not always the database fault..

When things are starting to get wrong, Database ( i.e DBA ) is always the first tier to blame. I am sure you have faced this situation, probably much more than once or twice.
Guilty as charged, until proven innocent, right?  (more…)

Bind variables in Oracle 11.2

A bit of an history before I begin…
Oracle 10.2 had exposed bind variables values passed to a SQL statement via a new view named V$SQL_BIND_CAPTURE. Nevertheless, to limit the overhead, Oracle captured the bind at most every 15 minutes for a given cursor. (more…)

Abnormal program behavior and massive log file sync

Historical performance data is extremely important when tuning application. This gives us the ability to instantly know when things start go wrong, and the ability to investigated over the past what start causing things to go wrong. Often I am feeling like a modern Sherlock Holmes, searching for criminals 🙂 (more…)

Bad screen design, bad performance

Recently one of my customers had loaded a new version into production. Immediately performance issues have started to rise. I have spotted a new query that became one of the top-3 heaviest SQLs running in the instance. Certainly not something that can be ignored… (more…)