How to shutdown Derby in-memory database Properly

Question

I'm using derby as an embedded database. Furthermore, I'm using it's in-memory database option for my unit tests.

What I can't figure out is how to properly shut down (A quick look at the code) the Derby database. I beleive I have it working for a standard database but I'm getting different exceptions when attempt similar code on a in-memory database.

I'm going to omit details, I'll add them if other feel are needed.

Basically, I'm trying to shut down my database in these two fashions where my in-memory database is consistently called "eh":

DriverManager.getConnection("jdbc:derby:memory:eh;shutdown=true");

then:

DriverManager.getConnection("jdbc:derby:eh;shutdown=true");

The former results in an exception but not the one expected. The details are:

java.sql.SQLNonTransientConnectionException: Database 'memory:eh' shutdown.

The latter results in

java.sql.SQLException: Database 'eh' not found.

Based on what I've been able to figure out, we want a SQLException but not the one we receive. On the other hand, the SQLNonTransientConnectionException error seems more appropriate but isn't the right type (though it is derived from SQLException) nor does it have the right state code. The state code end up being: 08006.

The example code I have illustrates that a SQLException with a SQL state of "XJ015".

Note: The example I'm referencing is: WwdEmbedded Program (Java Code).

Answer 1

XJ015 (with SQLCODE 50000) is the expected (successful) SQLSTATE for complete system shutdown. 08006 (with SQLCODE 45000), on the other hand, is the expected SQLSTATE for shutdown of only an individual database.

DriverManager.getConnection("jdbc:derby:;shutdown=true");

Shuts down the entire system and should result in XJ015.

Answer 2

The URL "jdbc:derby:memory:eh;shutdown=true" results in the expected 08006 error code, but doesn't actually remove the DB from memory. If later on, you try to create a new database with "jdbc:derby:memory:eh;create=true", you'll get an error saying that the database already exists.

Fortunately, as of Derby 10.6.1.0 (released on May 17, 2010), it is possible to actually drop an in-memory database using a URL of the form "jdbc:derby:memory:eh;drop=true". See the release notes and the page Using in-memory databases.

Answer 3

I believe that your first code example is fine. The SQL State difference that you are seeing, I believe, is because you are running Derby embedded, but the example code that you saw (with SQL state XJ015) was running in a client-server configuration.

As you noted, the SQLNonTransientConnectionException is a subclass of SQLException, so I am confused as to why you think you are not getting the right type of exception.