Monday, May 30, 2022
Long-term IT survivability - educational impact?
Wednesday, May 25, 2022
Back to live conferences
One of the reasons I decided to resurrect this blog is, to be fair, refresh my professional story-telling skills in English. As you may know, my native languages are Russian and Ukrainian, same for my family - and for the last two years I've been working from home. So, my English started to noticeably degrade.
If you work online - everybody is more or less on their own schedule, so you would rather send email instead of calling, there is no coffee breaks etc. As a result, I started to write a bit more eloquently, but technology conversations lag what I would call "the natural flow": I have to search for correct words instead of searching for the correct intonations.
And here comes the key topic: why would I care, considering that nowadays significant number of IT people just work from whatever they call their base (home/hotel/summer house/winter house etc)? My answer - because I learn from inter-person communication significantly more than I learn from written text! The way people tell their stories is much more than "just content" - it is all of their feelings/struggles/discoveries. It is a lot of extras that you cannot just dig our from the article or a blog post.
I've been speaking at various IT conferences for the last 20 years - and it always amazes me how much people undervalue live contact. I understand convenience of your own chair - but stepping out of it could bring you so much more!
In about a week I will be flying to Las Vegas for the first in-person conference since the beginning of COVID pandemia - BLUEPRINT 4D (June 6/June 9). I will have my own presentation there on Wednesday at 9 am - "Through the Looking-Glass: Database Views". As you can guess from the title, it will be SQL and PL/SQL-heavy - well, that's my normal style.
Hopefully, I will not stumble the same way I did at my first Oracle OpenWorld presentation (I had to simulate mic malfunction to buy some time and get back my voice :-) ). Two decades of experience are still two decades! And I really miss conversations with people, I really miss that great feeling of one big community that I had (and to be fair, that kept me within Oracle technology space).
Summary: person-to-person conversions are fun! Live events forever! :-)
Friday, May 20, 2022
Joys and Nightmares of a Tech Editor
2. Tech editor must always remember that it is not his book! The author has full rights to have his/her own opinion/style/favorites. As long as they are not factually incorrect, it is OK to not agree with the author - your role is to keep the author honest in front of the audience. I.e. you can point that something doesn't add up (or in some cases there are other approaches), but whether to follow this route - not your choice!
Monday, May 16, 2022
Return of a blogger (plus a bit of ORA-7445 [LpxMemFree()+200] )
Considering that "conference life" is picking up (two in-person events in June!), it is time to start writing something meaningful (yes, I am back to blogging after years of ignorance)!
To cover event previews I need a bit more prep time, while today I would like to share a small story (narrow, but very practical!)
At Dulcian we have a couple of systems still on Oracle 11g (yeah, I understand that it is outdated). And today one of my support people started to complain about ORA-07445. To be precise - ORA-7445 [LpxMemFree()+200]. And you know how much fun is to sort out those errors, especially considering my gut feeling ("I bet, XMLtype is misbehaving!")
Obviously, first two steps were obvious: Google and MOS.
Oook... Google gave me a direct hit - and I indeed was right, it was XML parsing issue - Doc ID 2220757.1
And in case you don't have MOS access - here is a code snippet to replicate (it should blow up with "end of communication channel" plus corresponding trace file):
declare
lv_text varchar2(6000);
lv_temp_xml xmltype;
lv_len number := 0;
begin
lv_text := '<LPCNotes Subject="Comments for LPC " Text="'
|| to_char(sysdate, 'dd-Mon-yy hh24:mi')
|| ' '
||lpad('A',4033,'A')
|| '" />';
lv_len := length(lv_text);
dbms_output.put_line('Length of the 3rd run is '||lv_len);
lv_temp_xml := sys.xmltype(lv_text);
end;
The proposed solution was to enable some kind of "old parser" - you can do it on either session of system level. Considering that everything else in our system worked fine, I added it via Dynamic SQL just before the problematic code, so it will be less overall system impact:
declare
lv_text varchar2(6000);
lv_temp_xml xmltype;
lv_len number := 0;
begin
execute immediate 'alter session set events ''31156 trace name context forever, level 1024''';
lv_text := '<LPCNotes Subject="Comments for LPC " Text="'
|| to_char(sysdate, 'dd-Mon-yy hh24:mi')
|| ' '
||lpad('A',4033,'A')
|| '" />';
lv_len := length(lv_text);
dbms_output.put_line('Length of the 3rd run is '||lv_len);
lv_temp_xml := sys.xmltype(lv_text);
end;
And the whole problem was gone! After a bit more digging I found that this kind of approach could help with a number of other similar ORA-07445 errors if you still on 11.2.0.4 (here is a doc from MOS: Bug 14822091)
Hope, it helps!
P.s. Footprint: in the doc they use hexadecimal level 0x400, but I prefer to use decimals (1024) for readability. What is funny, in the bug description whoever wrote it also used decimal - so, don't worry, it is the same stuff written differently.
Thursday, February 11, 2021
RMOUG-2021 Day#4
My today's presentation - "Managing Unstructured Data: Lobs in the World of JSON"
https://www.slideshare.net/MishaRosenblum/managing-unstructured-data-lobs-in-the-world-of-json
Tuesday, February 9, 2021
RMOUG-2021 Day #2
If anybody needs - here is my most recent presentation: "Hidden Gems of Performance Tuning":
https://www.slideshare.net/MishaRosenblum/hidden-gems-of-performance-tuning-hierarchical-profiler-and-dml-trigger-optimization
P.s. It was a pleasure to get back to RMOUG - even virtually!
Wednesday, April 5, 2017
Collaborate'17: Slides are available
https://www.slideshare.net/MishaRosenblum/developers-approach-to-code-management
More thoughts/comments about the conference are coming! To be continued...