This is a short article I write because it would have saved me some significant time had I been able to google it (no time-travel google (yet) – find articles you will write in the future). So maybe somebody in the future will find this useful 
.
What we were doing is to use a Microsoft Business Intelligence/Reporting Server to report on data in an Oracle production database.
Creating the OLAP cubes in the MS system, everything worked fine until I tried to pull in aggregate data over a date field from the database, giving me the mysterious “Not a legal OleAut date” error message that can be found in the various forums, but none in the context of OLAP cubes. >> more…
Recently we ran into a problem caused by Oracle’s DATE Type, because it’s granularity is only seconds and not milliseconds. Our goal was to get the newest of a group of messages using SQL.
The first attempt, simply using the date, did work only as long as we didn’t have messages coming in at the same second (else, it would return more than one message). For the second approach we used the JDO-ID, which gets automatically incremented and assigned to each persisted object (i.e., to each message). So we assumed it will assign higher IDs to newer objects, and as this ID is unique, always give us exaclty one result. But strangely, this worked only in some cases. Here’s an excerpt of a discussion of two developers, that explains why: >> more…
