Posts tagged dml
Today I had a request to implement a generic logging mechanism for all changes of data (DML) in an ADF application. The log needs to be persisted in a database table. This application uses ADF-Business Components and an Oracle Database. My first idea was to use database triggers for all tables (insert, delete, update for each row) and write the data to a log table. However that was not generic enough because this has to be implemented on every new table. I had to come up with an ADF solution. It’s basic, no rocket science, but useful (more…)
Introduction Within ApEx for a while it has been possible to create a page (more specifically, a form) based on a procedure. A procedure enables you to build in more logic than a simple DML statement or otherwise. My example is relatively simple in that when I want to book an appointment with somebody, I do not want this appointment to overlap with somebody else’s. Maybe I even don’t want my appointment to be directly after or before another one, and want a 15 minute break.
Build the procedure This kind of scenario is not easy to realise if you don’t have a plan. The plan is therefore to build an INSERT statement (into a procedure, not a function!) that is only actually executed when there is enough room for my new appointment – in terms of time – in my agenda. Building this procedure is done in the Object Browser area of Apex (Home –> SQL Workshop –> Object Browser; press Create). To check that there are actually no overlaps you need to know when the appointment starts and how long it will take. (Loads more additional features could be added, I am trying to keep the example simple for now). This justifies at least 2 IN-parameters for a procedure to be built, starting More >