Oracle Database SQL – Recursive Subquery to inspect events in football matches – find the MVP

Lucas Jellema

In a recent post (  I described how we can use the new Oracle Database 12c MATCH_RECOGNIZE operator to spot patterns in records and derive results from those patterns. I used the MATCH_RECOGNIZE to find the most valuable player in a football team (US readers: I mean the sports that […]

Oracle SQL – Finding free adjacent seats in an airplane, using Subquery Factoring, Analytical Functions (LISTAGG and LEAD), Outer Join, PIVOT and good old INSTR

Lucas Jellema 1

Using Oracle SQL to resolve meaningful and slightly less serious challenges is one of my favorite (semi-)professional pastimes. In the last two weeks, I have been presenting on various topics including Oracle SQL to audiences in six cities all across India as part of the OTN Yathra 2013. These presentations […]

AMIS Masterclass Advanced SQL – scherp je SQL skills in een pittige en praktijkgerichte dag – maandag 10 december

Lucas Jellema

Of je nu ‘klassieke’ Oracle applicaties ontwikkelt, met APEX bezig bent, een SOA landschap inricht of een Java/JEE (bijvoorbeeld ADF) applicatie bouwt: het fundament van veel van wat je doet is de database. En de crux van optimaal gebruik van de database is en blijft SQL. Dit bepaalt performance en […]

The APEX of Business Value… or: the Business Value of APEX? Cloud takes Oracle APEX to new heights!

Lucas Jellema

The attraction of APEX has increased tremendously with the recent launch of the Oracle Cloud. APEX already supported departmental development and deployment of business applications with minimal involvement from the IT department (only a database needed be made available). Positioned as the ideal replacement for MS Access, APEX probably has […]

Oracle RDBMS 10GR1: solution to avoid character encoding in XML with UPDATEXML

Betty van Dongen

On a recent project, I ran into a problem with an XML document, that had to be enclosed within another XML document, generated from a database query. The problem I ran into was the character encoding of the XMLElement function, which eventually was worked around with UPDATEXML. In this blog […]

Using SQLite databases in iOS apps

Recently I’ve been working on an application that has to store a significant amount of data on a device. When storing data on the iPhone there are a few options.  You can use straight up text or xml files that are then read when the app runs, you can use […]

ADF: The best way to indicate for records in a table the existence of details – or: the importance of up-to-date SQL knowledge

Lucas Jellema 3

An interesting discussion arose in one of the projects I am involved in. The functional requirement at stake: show records in a table. In one of the columns, show an indicator (checkbox for example) that signals whether or not that particular record has a specific type of details associated with […]

2 dagen seminar door Steven Feuerstein: Best of Oracle PL/SQL (8 en 9 december)

Robbrecht van Amerongen

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 […]

Data Integriteit anno 2011 – Hands-on met Toon Koppelaars en RuleGen 3.0 bij AMIS op dinsdag 27 september

Lucas Jellema

datum: dinsdag 27 september; 16.30 uur locatie: AMIS, Edisonbaan 15, Nieuwegein sprekers: Toon Koppelaars en Lucas Jellema Het belang van data integriteit behoeft geen toelichting – als het goed is. Vrijwel iedere enterprise applicatie is gebouwd op het fundament van een database. Robuustheid van die database en absolute betrouwbaarheid van […]

Using SQL UNPIVOT to prepare data for dynamic ADF Faces User Interfaces

Lucas Jellema

The UNPIVOT operator was introduced in Oracle Database 11g – see for example: In Oracle, the UNPIVOT operation is the process of turning Columns to Rows. Put simply, by applying the UNPIVOT operator to a number of columns, every row is split into that same number of rows. Each […]