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 →
Why did the chicken cross the road?
Because 1 > NULL AND cross_the_road()…
I bet you have heard about the chicken and you know at least a dozen reasons why it had crossed the road. I wouldn’t bet, though, that you have heard about the three-valued logic. And this one is interesting, it even makes the chicken cross the road. The answer to the above question could also be given as: Because it (the chicken) didn’t short-circuit evaluate. What does it all mean? Continue reading →