Back in the days, when I was just beginning working as an Oracle developer, I used to view Oracle Database Server as such a great piece of software to the extent where I wouldn’t even consider that a problem which I’ve just encountered wasn’t my fault, but Oracle’s bug!
Why am I bringing this up, you might ask? Well, a few weeks ago I’ve stumbled upon a weird bug in Oracle. I was using Oracle 18.104.22.168.0. Take a look at the below example: Continue reading →
Getting Referential Constraints using DBMS_METADATA
The GET_DDL function of the DBMS_METADATA package, supplied by Oracle, is a nice tool to extract the DDLs of database objects. This quick guide will show you how to deal with the problem of exporting referential constraints – what problem, I hear you saying? Continue reading →
In my last post, I’ve challenged you with a quiz about package dependency. The question was about when a dependent object will be invalidated by Oracle when the package on which it depends is recreated.
Returning a BLOB from a Java Method Embedded in a Database
You’re about to learn your future
Oracle supports embedding Java classes in its database. Different SQL types are mapped to corresponding Java classes to allow us to make the most of this feature. Author of the following question on StackOverflow:
had an issue with returning a BLOB object from Java method back to PL/SQL context. In the beginning, I didn’t even think you could return a new BLOB object from an embedded class. Fortunately, there was a BLOB in my Java, too. Continue reading →
Getting the Top-N Records From an Ordered Set & The New Row Limiting Clause – 11g & 12c
and a cup of tea if you’re lucky
I bet my cup of raspberry-juiced black tea that, somewhere along your journey with Oracle, you had to write a query which was supposed to return only the top-n rows from an ordered set. Unlike some of the other databases, MySQL, for instance, Oracle does not provide a dedicated solution to this problem.
At least, not before the 12c hit the stage.
Before I introduce you to the nice Row Limiting Clause, let me show you why the first solution that comes to mind to solve the problem at hand, in Oracle’s versions prior to 12c, is not the right one, and what voodoo tricks one has to perform to achieve the expected result. Continue reading →