Hotsos 2010 – About swag, the Oscars and other stuff
Its Sunday and its raining outside. The nice weather on Saturday (approx. sunny / 20 degrees Celsius) has gone. After a decent flight on Friday where I actually made it to switch in Houston from the international Continental flight, going through customs and pick the next one, a domestic Continental Express flight, within the boundaries of 1 and 1/2 hour. I was so fast that switching for one flight to the other, that apparently my luggage didn’t manage to travel with the last flight. So after I found out that my luggage was still somewhere in Houston, I got from Dallas Love Field to the Omni Hotel in Las Colinas, Irving, where the Hotsos conference will be held again. The whole area is a bit in shambles because they are rebuilding a lot of the environment. While getting to the Grapevine Mills mall yesterday, I noticed that they also a building a new Irving Convention Center along the highway. Another addition to the already crowded Dallas/Plano/Irving Metroplex.
Part of the Puzzle: Oracle XMLDB NFS Functionality
This story is long overdue and no its NOT about the Oracle Database 11g Database File System (DBFS). Its about an “undocumented” NFS functionality that, maybe someday, will be serviced by the XMLDB XDB Protocol Adapter. This post is “long overdue” because the actual attempts to try to figure it out were done during the bank holidays between X-mas and new year 2009.
So what is it all about. I once discovered in the Oracle 11gR1 documentation a small entry in the xmlconfig.xsd XML Schema regarding NFS elements that look like that they are or will be used for enabling NFS functionality based on the Oracle XMLDB Protocol Server architecture. In those days, when Oracle 11gR1 was just of the shelve, I made a few attempts, based on the xdbconfig.xsd XML Schema to adjust the corresponding xdbconfig.xml file that controls the XDB Protocol Server functionality, to see what would happen. At that time I only was able to get this far (see the picture) and I promised myself that I should look deeper into it trying to figure out if I could get it working and/or what the concepts were that made it tick in the XMLDB architecture but somewhere down the line I just didn’t come to it and it got “forgotten” by me due to my daily DBA workload.
Click picture to enlarge
Small Intermezzo Towards Miracle OpenWorld 2010
Created a small YouTube introduction movie as requested by Moans for the Miracle OpenWorld 2010 event this year. I am happy they more or less resolved their issues with Oracle Legal regarding the naming for the event (see the movie and news section on the Miracle OpenWorld 2010 main page).
Anyway, made a small attempt (in HD) to tell a bit about XML on YouTube.
As said:
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“An exploration in mending and gluing things together, while it absolutely doesn’t make any sense what I am saying, but then again, who cares…its bogus anyway…”
Hope to CU around somewhere this year.
ORA-31098: Internal event to turn on XDB tracing
“Do not document”…
…if not only due to that comment, it is a very interesting event, if not only that it seems that it is used for multiple items and not only tracing. I tried to figure out what I could do with this event regarding the XDB Protocol Server trying to figure out how it works and to trace a partially documented/undocumented feature in the manuals that makes use of the XDB Protocol Server.
The XDB Procotol Server architecture is used for more than the (APEX) PL/SQL Gateway. It also supports HTTP, FTP and WebDAV (so called) “servlets” and a hook-in into C kernel library that enables the XMLDB Native Database Web Service (NDWS).
The following should only be done asked by Oracle Support and/or are at your own risk. Always test on a test environment (so if when the database is corrupt is not a big deal)
Anyway, “events” can be set on session and system level and/or via the oradebug facility. Julian Dyke has a good post on the basics. As Julian describes, there are four types of numeric events: Immediate dumps, Conditional dumps, Trace dumps, Events that change database behavior. The “fun” with the ORA-31098 seems that is used for multiple things. It at least creates DDL scripts in trace file during dbms_xmlschema registration and it also traces XDB Protocol Server issues. During X-Mas and new years eve I had some time, so I tried to figure out some of them…
Structured XMLIndex (Part 3) – Building Multiple XMLIndex Structures
You will probably never build only one structured XMLIndex. A practical use case would be an unstructured XMLIndex, indexing the semi-structured parts of your XML, multiple structured XMLIndexes, indexing the highly structured XML islands of data and maybe even a Oracle Text Context index indexing unstructured XML data.
So the next example’s will show how to build an unstructured XMLIndex and build multiple structured XMLIndexes on top of the first one. Also it will give some examples on what to do if you have made mistakes and/or how to apply some maintenance on the XMLIndex structures. You start of by determining which sections should be addressed by the Unstructured XMLIndex and via path subsetting restrict the index to that part (also see “Oracle 11g – XMLIndex (Part 2) – XMLIndex Path Subsetting” for more info on path subsetting). There should be, I think, a good reason for indexing the same node path via multiple structured or unstructured XMLIndexes. One I can think of is to support different kind of XML Queries, but be aware that it, multiple XMLIndex structures on the same nodes, will come with an extra index maintenance overhead.
Anyway, lets say you want most part (haven’t used path subsetting here for the unstructured XMLIndex, but as said I should have done) of the XML document indexed via a unstructured XMLIndex and an extra of two structured XMLIndexes on top of the domain XMLIndex…
