I spoke at a one day DOUG meeting yesterday. It was pretty cool. Very small intimate group of about 50. The speakers were Nitin Vengurlekar, Charles Kim, Cary Millsap and myself. All are Ace Directors and either work at Viscosity or Enkitec. As a bonus, Tanel Poder showed up to weigh in on some open discussion. Anyway, I thoroughly enjoyed it. I promised the group I would post my slides and a zip file with (more...)
Here’s a quick rundown of places I plan to be during the week.
|Sunday 9/28/14 3:30||Expert Oracle Exadata: Then and Now [UGF6626]||I’ll be participating in the Exadata Then and Now Panel with Tanel Poder, Andy Colvin, Martin Bach, Karl Arao, Frits Hoogland and anyone else we can drag in. The idea is to get book authors from “Apress Expert Oracle Exadata” version 1 and version 2 (due out by the (more...)|
I started looking into In-Memory on RAC this week. Data can be distributed across RAC nodes in a couple of different ways. The default is to spread it across the available nodes in the cluster. So if you had a 2 node cluster, roughly 50% of the data in your table or partition would be loaded into the column store in each of the 2 instances.
SYS@dw1> alter table kso.skew inmemory; (more...)
In preparation for our upcoming 12c In-Memory Webcast @CaryMillsap, @TanelPoder, and I solicited questions from members of the universe at large on the interweb. We got a question about how In-Memory works with the 12c multi-tentant option and it got me thinking so I gave a quick try. As it turns out, it works about as you would expect. The basic idea is to turn it on for the container DB (which is where the (more...)
Oracle’s 126.96.36.199 was released a few weeks ago (You can download it from OTN here: Oracle 188.8.131.52 Download). While technically a minor point release, it contains a couple of major features that would normally be rolled out in a more substantial version change like 12cR2 or perhaps V13. Of course the most highly anticipated feature is a new option (Oracle In-Memory Option) that provides a column (more...)
I keep hearing about “Center of Excellence”. The term makes no sense to me. What does it mean? The middle (center) of wonderfulness? A place (center) where one goes to become excellent? Lately I’ve been hearing it used to describe our lab which is just a collection of computer equipment. In our case it’s a bunch of Oracle Engineered Systems. Our lab is really cool because we have a bunch of bad ass toys. I (more...)
Just a quick post on a new Exadata feature called Zone Maps. They’re similar to storage indexes on Exadata, but with more control (you can define the columns and how the data is refreshed for example). People have complained for years that storage indexes provided no control mechanisms, but now we have a way to exert our God given rights as DBA’s to control yet another aspect of the database. Here’s a link to the (more...)
I saw this very odd statement on an SAP system last week.
SELECT /*+ AVOID_FULL ("/bic/xxx") */ * FROM "/BIC/XXX" WHERE "/BIC/XXX"=:A0
I had never seen that hint before so I thought I’d do a little investigation. First I did a quick check on a test case to see if it worked.
SYS@DEMO1> select /*+ avoid_full(a) */ count(*) from kso.skew a where col1=234657; COUNT(*) ---------- 32 SYS@DEMO1> @x (more...)
The Oracle 11g parameter parallel_degree_limit is designed to put a cap on the maximum DOP for a statement.
The Oracle Data Base Reference 11g Release 2 (11.2) says this:
A numeric value for this parameter specifies the maximum degree of parallelism the optimizer can choose for a SQL statement when automatic degree of parallelism is active. Automatic degree of parallelism is only enabled if PARALLEL_DEGREE_POLICY is set to AUTO or LIMITED.
But that’s not (more...)