column_value = NVL(:bindewert, column_value)
ORA-01489: result of string concatenation is too long
I follow a few bi-language blogs but I do wonder if English speakers may find this post when googling the issue. For me it's on page 1 when googling "listagg clob", but I knew what keyword to search (more...)
When I setup an application, I usually use Dimitri Gielis' method, so instead of using "real tabs", I use a List and display that list as Tabs.
For each of the "Tabs", I also create Page Groups, just to keep things organized. (more...)
-- rekursive Variante mit connect by levelselect level id
from dual-- rekursive Variante mit subquery factoringconnect by level <= 10;
Following the database design championship playoff over on the PL/SQL Challenge, one player asked:
“Could you please advise me some resources (boooks, courses) so that I can improve?”
Of course I can! This is what I love to hear – people looking for resources they can use to increase their skills. This is information I’m sure others will benefit from, so here goes:
select materials from my_readings where topic = 'Database design';
Moving through some observations of an ongoing investigation tackling the easiest ones first.
Previously I observed the slow execution of a recursive delete of statistics history but coming not from MMON but from a number of application processes which should have only been calculating stats for their own partitions.
Statement was sql id 9v9n97qj8z1dg:
delete /*+ dynamic_sampling(4) */ from sys.wri$_optstat_histhead_history where savtime < :1 and rownum <= NVL(:2, rownum);
where rownum <= nvl(:rn,rownum)
The "ADF book" is a compilation of German lectures, articles and workshop tutorials in Oracle ADF (some of the contributions are in English!). The authors are members of the German ADF community. The time frame covers the years 2010 to 2014. The project "ADF book" was implemented by a team of staff from partner companies and Oracle.
40 authors wrote 70 contributions on 1400 (more...)
Yesterday I mentioned issues with a recursive delete operation on statistics history.
This is a quick illustration of the last points I made on that post regarding the lack of a COUNT STOPKEY optimisation because of the use of NVL.
COUNT STOPKEY is an optimisation which allows processing to stop once the target number of rows has been reached.
create table t1 as select * from dba_objects; alter session set statistics_level = all; (more...)
Today I helped resolve a problem quickly but to the detriment of my understanding of exactly what was going on and why.
And as part of the quicker resolution, I had to destroy the evidence which would have helped understand better.
So… now need to go back and figure it out if I have time to model it properly, etc.
Here’s what little I know so far.
What happened was that there were a number (more...)
The liibrary contains around 50 PL/SQL packages as well as a few types. There are no table dependencies, which reflects the general-purpose nature of the utilities. Jeffrey Kemp has a great guided tour of the library which highlights some of (more...)
The results of the first ever database design championship playoff were announced today. Huge congratulations to Sean Molloy, Pavel Zeman and Justin Cave for taking the top three spots. Also thanks to everyone else who’s taken part in the quiz, answering questions, adding to the discusions and pointing out my mistakes ;)
With this in mind here’s a some of the facts and figures from 2014’s database design quizzes, along with related trivia:
-- How (more...)
Recently I've been trying to share my blog posts via LinkedIn but I'm always unsure which of the seven APEX groups I'm a member of I should post to.
It turns out only the SIG groups are owned by those involved with the APEX development team, namely David Peake (more...)