Continuing in the beard-scratching theme of Unix related posts (previously - awk), here’s a way to graph out the I/O profile of your Oracle database via the Oracle metrics in gv$sysstat, and gnuplot. This is only the system I/O as observed by Oracle, so for belts & braces (or to placate a cynical sysadmin ;-)) you may want to cross-reference it with something like sar. First, a pretty picture of what you can get:

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More of a unix thing than DW/BI this post, but I have a beard so am semi-qualified…. The requirement was to improve the performance of some ODI processing that as part of its work was taking one huge input file, and splitting it into chunks based on content in the file. To add some (minor) spice the file was fixed width with no deliminators, so the easy awk answers that I found on google weren’t applicable.

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Last month I wrote about a problem that Informatica as part of OBIA was causing us, wherein an expired database account would bring Oracle down by virtue of multiple connections from Informatica. I raised an SR with Oracle (under OBIA support), who after some back-and-forth with Informatica, were told: This is not a bug. That the two error messages coming back from Oracle are handled differently is the result of a design decision and as such not a product fault.

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Jeff Atwood of Coding Horror fame observed: This is sage advice (if a little crude :-)) to bear in mind when building reports for users.

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As Twitter learnt yesterday, you should always sanitise user input. I was amused to see My Oracle Support doing so….recursively :) The apostrophe in “doesn’t” got escaped once, and then again, and then again, and then again, and then again ……

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Here’s one in the series of stupid things I’ve done but which Google has thrown no answers, so I post it here to help out fellow idiots. Today’s episode involves our SCM tool, TortoiseSVN. I’d been happily using it for over a year, when suddenly I couldn’t commit any more. I could browse and checkout to my heart’s content, but when I tried to commit, boom: Commit failed (details follow): Authorization failed

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This query, based on AWR snapshots on sys.wrh$_sysstat, includes in its metrics the I/O read throughput for a given snapshot duration. However it’s important to realise the huge limitation to this figure - it’s an average. It completely shoots you in the foot if you’re looking at capacity requirements. Consider this real-life example extracted from the above query: [sourcecode] Timestamp Total Read MBPS =========================================== 14-SEP-10 05.15.12.660 113.748 14-SEP-10 06.00.40.953 202.250 14-SEP-10 06.

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I’m a geek. I like understanding things in their absolute entirety. It frustrates me to have to make presumptions or assumptions about something. I like to get down ’n dirty and find out what makes things tick. So that necessitates reading manuals. And unfortunately, Oracle don’t make that easy all the time. Some of the manuals are not very good, and others are difficult to find. Given the complexity of the OBIEE stack and proliferation of terminology and product names, sorting the wheat from the chaff can be a headache.

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Introduction We’re in the process of implemention Resource Manager (RM) on our Oracle 11gR1 Data Warehouse. We’ve currently got one DW application live, but have several more imminent. We identified RM as a suitable way of - as the name would suggest - managing the resources on the server. In the first instance we’re looking at simply protecting CPU for, and from, future applications. At some point it would be interesting to use some of the more granular and precise functions to demote long-running queries, have nighttime/daytime plans, etc.

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This problem, which in essence is bad behaviour from Informatica bringing down Oracle, is a good illustration of unintended consequences of an apparently innocuous security setting. Per our company’s security standards, database passwords expire every 90 days. When this happens users are prompted to change their password before they can continue logging into Oracle. This applies to application user IDs too. It appears that Informatica 8.6.1 HF6 (part of OBIA 7.

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A very short blog post to break the drought, but I didn’t hit any google results for this error so thought it might be useful to record it. In BI Publisher 10.1.3.4, trying to install the Scheduler (Quartz) schema, I got this error: [sourcecode]Schema installation failed while creating tables. Schema may already exist. Please remove the existing schema or choose another database and try again.[/sourcecode] To me, the error text is a bit unhelpful.

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@alexgorbachev tweeted me recently after picking up my presentation on Performance Testing and OBIEE. His question got me thinking, and as ever the answer “It Depends” is appropriate here :-) Why is the measurement being done? Without knowing the context of the work Alex is doing, how to measure depends on whether the measurement needs to be of: - The actual response times that the users are getting, or The response times that the system is currently capable of delivering This may sound like splitting hairs or beard-scratching irrelevance, but it’s not.

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Here are a couple of little unix scripts that I wrote whilst developing my performance testing OBIEE method. They’re nothing particularly special, but may save you the couple of minutes it’d take to write them :) Note that some of this data is available from Usage Tracking and where it is I’d recommend getting it from there, databases generally being easier to reliably and repeatably query than a transient log file.

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OBIEE 11g is going to be officially launched on 7th July (this year!) in London: Launch Event: Introducing Oracle Business Intelligence Enterprise Edition 11g h/t to Twitter and blogs (including an Oracle-branded one) this morning. Good news travels fast! :-) Looks like John Minkjan won the bet, did he know something we didn’t? ;-) (although is “Launch” the same as “GA”?)

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Here’s my presentation “Performance Testing and OBIEE” that I gave at the RittmanMead BI Forum 2010: Performance Testing and OBIEE.pptx It’s a Powerpoint 2007 file (pptx) for which you may need the Microsoft PowerPoint Viewer 2007. I’ve included copious notes on each slide which hopefully cover the gist of what I talked about when I was delivering it. There are also a handful of funky animations which is why I’ve left it in pptx and not exported to PDF or other format (sorry Open Office users).

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I delivered my first presentation today, at the RittmanMead BI Forum.I was really nervous in the hours and minutes leading up to it, but once I got up there and started talking I actually quite enjoyed it. If you were in the audience, I’d love some feedback in the comments section below, particularly any “constructive criticism”. I obviously didn’t make too much of a mess of it, as I was awarded “best speaker” of the event, which was a great honour.

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I’ve just returned from the RittmanMead 2010 BI Forum which this year was at the Seattle Hotel in Brighton Marina. The event was limited to 50 attendees, and I think this was a good number. The event was explicitly pitched at a very technical expert level, and the audience very much represented this. Whereas at a larger conference you may find the odd manager wandering around pretending to be technical ;-) this event was most definitely not pitched at such types.

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Troubleshooting EBS-BI integrated authentication can be a tiresome activity, so here’s a shortcut that might help. If you suspect the problem lies with EBS then you can leave OBIEE out of the equation. Login to EBS Use FireBug or Fiddler2 to inspect web traffic as follows: Click the BI link from EBS Should be first a request to EBS server, which returns 302 and redirects to http://<bi server>:<port>/analytics/saw.dll?Dashboard&acf=101507310 Record the value of acf (eg 101507310)

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What’s going on here? The username/password is definitely valid, proved by the sqlplus connection. Configuring DAC in OBIA 7.9.5.1: [sourcecode] What can I do for you? 1 - Enter repository connection information 2 - Test repository connection 3 - Enter email account information 4 - Send test email 5 - Save changes 6 - Exit Please make your selection: 1 These are your connection type choices: 1 - MSSQL 2 - DB2 3 - Oracle (OCI8) 4 - Oracle (Thin) 5 - Keep current ( Oracle (Thin) )

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This is a note-to-self really. When playing around with Oracle and something’s not working - RTFAL: Read The Flippin Alert Log! After resizing a VM I was getting this problem: [sourcecode] [oracle@RNMVM01 ~]$ sqlplus / as sysdba SQL*Plus: Release 11.2.0.1.0 Production on Sat Apr 24 17:44:44 2010 Copyright (c) 1982, 2009, Oracle. All rights reserved. Connected to an idle instance. SQL> startup nomount ORA-00845: MEMORY_TARGET not supported on this system SQL> [/sourcecode]

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