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...)
I replaced my OtterBox Defender with an i-Blazon Prime case when upgrading to the iPhone 6. It appeared a good option, and for 4 months it was fine. Yesterday, the latch broke and my iPhone fell to the ground as a walked. Fortunately, my iPhone landed flat, the i-Blazon plastic case absorbed the impact, and my iPhone was undamaged.
Here’s a photograph of the damaged case:
While I wanted to order only the belt portion (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...)
So I've started one here with a very basic form/report:
At the moment it's just a list of those I happened to have bookmarked over time, in one place that others could use and perhaps contribute to.
Depending on feedback I (more...)
PL/SQL championships are held quarterly, but the less frequent SQL and Database Design quizzes are currently held annually. Thanks to persistence and maybe a bit of experience, I was eligible to compete in both.
Unfortunately do to a timing issue, (more...)
I thought I'd chime in after some recent experiences were helped along by the use of Twitter, a tool it seems many are underutilising.
Exhibit AI had an afternoon of generating JSON with SQL using LISTAGG and I kept facing this issue of being limited by 4000 characters. Knowing I occasionally (more...)
Until we get our shiny new 12c database running on its shiny new box (and all the data shifted to it), we are living with a mix of databases. To begin with, the data we managed was mostly AU/NZ and Europeans stuff, and the character set (more...)
I had a registration form in Apex which asks the applicant to enter their Date of Birth in a date item; I then needed to calculate how old they would be at the start of the event, which determines a number of rules, such as whether we need to obtain their parent’s permission.
In my first release I implemented this with a Dynamic Action which ran SQL something like this:
select round(months_between(start_date ,to_date(:P1_DATE_OF_BIRTH,'DD-MON-YYYY')) / 12,1) from (more...)
- in 10g führt die Statistikerfassung bereits bei weniger als 255 Spalten - nämlich bei etwa 165 Spalten - dazu, dass mehrere FTS erforderlich werden, um die Daten einzulesen.
- das (more...)
I promised my students an example of writing xquery statements in Microsoft SQL Server. This post builds on two earlier posts. The first qualifies how to build a
marvel table with source data, and the second qualifies how you can create an XML Schema Collection and insert relational data into an XML structure.
You can query a sequence with xquery as follows:
DECLARE @x xml; SET @x = N''; SELECT @x.query( (more...)
Working through Chapter 7 of the Querying Microsoft SQL Server 2012 book for Microsoft’s Exam 70-461, I found the XML examples incomplete for my students. I decided to put together a post on how to create:
- An XML Schema Collection type.
- A table that uses an XML Schema Collection as a column’s data type.
- An example on how you can transfer the contents of a table into the XML Schema Collection.
This post assumes you (more...)