Knowledge Center Database Administration
UKOUG 2011 is nearby and one of the coolest things in Oracle 11g and onwards is, IMHO, a functionality called XDB Repository Events. Most of you probably know that based on XMLDB functionality in the database, the database also can be used in a File server kind of way by enabling the XDB Repository HTTP/FTP or WebDav functionality via DBMS_XDB. XDB Repository Events are a kind of “triggers” that enable you to automatically trigger/do something based on the events triggered in this file/folder environment. For example, it is possible to automatically create duplicate files in the XDB Repository or secure them. Other possibilities are to read the content of such a file and insert that content, on the fly during the copy/paste action, into a relational table.
Most APEX enthousiast know of the PL/SQL Gateway, which is a small part of the functionality that is called the XDB Protocol Listener. Besides PL/SQL support, it also enables you to secure your data, as mentioned, trigger actions based, for example on MIME type, mount your database as a Logical Volume (currently only via WebDAV, eg. DAVFS) of your operating system. The XDB Protocol Listener can support your own solutions based More >
I was lucky enough to get my hands on the Method-R Profiler and had a test drive with it. So first of all what is it? As you might expect a profiler, a profiler for Oracle performance problems. The tool makes use of Oracle’s trace facilities. If you have a performance problem with the database or a specific issue in you code, you are able to set a specific part of your code, or if must be, the whole database in trace mode. The database will write the output of your trace to the UDUMP, user dump, destination or in the trace directory of your database diagnostic section on the database server, depending on your database version.Consistent Analysis
Pete Finnigan has a nice post about how you can achieve this called “How to set trace for others sessions, for your own session and at instance level“. As also is mentioned in this post, the Oracle TKPROF tool can be used to analyze the generated trace files. One of the disadvantages, IMHO, is that if you give such a TKPROF generated report to, lets say 10 Oracle (DBA) performance interested people, you will get afterwards 10 different analyses regarding what is reported in those reports. This is, among others, also caused by the fact More >
In (rman) incrementally updated backups, only incremental backups are done after the first full backup to the Fast Recovery Area. From 11gR2 on the incremental backup pieces will get the same tag as the datafile copies, and that’s actually different behaviour from pre- 11gR2 versions of the database.
I stumbled on this different behaviour when a backup script, that worked perfectly on 11gR2, got ported to 10gR2 and 11gR1 ( 11.1.7 ). The script contains a system cleanup of all incrementals, done before a certain date, specifying the tag of the copy [ 'COPY_DATABASE' ]. On 11gR2 the inc1 backups got deleted fine, but the delete on 10gR2 and 11gR1 just wouldn’t work.
By checking v$backup_piece…
select distinct tag
…and getting no result, it became clear that the tag of the copy datafiles, was’t also the tag of the incrementals.
Once I knew, it was easy to correct the problem.
I just added the tag of my copy datafiles to the incremental backup, and that did the trick. All incrementals that were supposed to get cleared from the pre-11gR2 system, were deleted. The incrementals without tag, already on the system, were deletedMore >
If you, like me, like to use (rman) incrementally updated backups, a copy of all datafiles will be present in the Fast Recovery Area. That becomes quite handy if you are in sudden need of extra disk space for your database, and the FRA still has ample space left. By switching one or more datafiles to the copy in FRA, you can very quickly use this extra disk space for your database, while not even having to shut down. I developed a view to generate all the rman commands to execute the switch to FRA, and the switch back to it’s original location and name. Use it at your own discretion.
CREATE OR REPLACE FORCE VIEW rman_switch_datafiles
||'Â switch datafile '||file_id||' to copy in FRAÂ '||chr(10)
||'sql ''alter tablespace '||tablespace_name||' offline'';' ||chr(10)
||'switch datafile '||file_id||' to copy;' ||chr(10)
||'recover datafile '||file_id||';' ||chr(10)
||'sql ''alter tablespace '||tablespace_name||' online'';'||chr(10)
, More >
In dit tweedaagse seminar neemt Steven Feuerstein je mee ver voorbij de basismogelijkheden van PL/SQL. Steven zal tijdens dit seminar de best practices behandelen die hij op tientallen plekken in de wereld heeft verzameld en die hij ook mede door zijn nauwe samenwerking met het PL/SQL product team van Oracle kan verifiÃ«ren en aanscherpen. Hij laat via code-voorbeelden en interactieve sessies zien hoe je als ontwikkelaar in staat bent om snel, hoogwaardige, goed onderhoudbare en uitbreidbare applicaties kunt maken.
Er is tijdens dit seminar voldoende ruimte om vragen te stellen en ideeÃ«n met Steven Feurestein uit te wisselen.
Bij dit seminar zijn de volgende zaken inbegrepen:
- Een exemplaar van het boek Oracle PL/SQL Programming (5th edition) van Steven Feuerstein (twv â‚¬71,-).
- Een PL/SQL quiz onder leiding van Steven Feuerstein met leuke prijzen.
- Ook ontvang je een gratis jaarabonnement op het PL/SQL Channel. Hiermee heb je toegang tot 27 uur videotraining (normaal $395).
Last day of Oracle Open World and I am currently attending the last presentations. The first presentation, “Oracle XMLDB: A noSQL Approach to Managing all your Unstructured Data”, deals with the no-SQL approach and using Oracle XML DB in the context of using it with “Big Data”, that is unstructured data. The title of the presentation is “a bit” misleading due it reference to noSQL data handling. XML is mostly used in the area’s of structured, data centric, semi-structured an unstructured, that is document centric data. Due to the flexibility of XML, it can be used for bridging those data content forms. Via the XDB repository, xmltype storage and xmlindex, that content can be moved into the XML DB part of the Oracle database, mapped and categorized. You can use repository events to shred and filter this map while the data is going in regarding interfacing via FTP or WebDAV. In all the presentation addressed a lot of already known fact of the XMLDB functionality and not really how to use it with huge amounts of unstructured data.