Turn off variable replacement in SQL+

set define off;

Drop Column

alter table <tablename> drop column <column_name>
Also look here.

Rename Column

alter table <tablename> rename column <column_name_old> to <column_name_new>;

Using SQL+ Command Line tool

Connect:

connect scott/tiger

Excecute a sql-file

@path/to/myscript.sql
also see this

The Logfiles then hinted me, that Hibernate chose the SequenceHiLoGenerator for ID Generation.

Looking through the web here, here and here , I came  close to understanding the algorithm.

The idea is to not touch the DB everytime an ID is needed but to “reserve” a block of numbers, using 50 as a default block size. Reservation is done by: 50*CurrentSequenceValue. Then Hibernate adds 1 to this base value everytime a new id is needed. When it has added 50 times, a new block is reserved using a fresh sequence value.

Perhaps this picture makes it clearer:

All of this configurable of course. I am a little surprised that this is the Hibernate default though.

Eventually I discovered that I did not receive any more backups.

Doing backups manually (and downloading them) worked fine. If I decided to not not download them, but to email them, I got an error stating:

Only variables should be passed by reference

Oh well, that did not sound good. The error wasn’t that helpful either.

Some sketched solutions I tried (and didn’t work) were:

• Increase memory limit
• Rewrite some plugin code

I don’t want to go into the embarassing details here, because the solution was … ehhhh … simple.

Solution

In the managing UI of my provider (hosteurope) you can define a standard email adress, which I did not know of. Set it and everything worked fine! The email adress configured within wordpress does not seem to suffice.

I am a little sad, that this wasn’t obvious from the logs or the UI. Or the provider could have simply predefine a standard adress, that would have reached my primary adress (catch all).

Funny thing is, that I did find this only because I was about to install some other DB backup tool, that pointed me to that potential problem.

You can download them here aswell.
The slides and my talking were recorded and I’m really looking forward to see this recording.

[UPDATE]

The recording can be viewed here.

Or here:

Looking forward to the next talk.

@EJB(beanName="MyStalelessSessionBean")
public void IMyStalelessSessionBean (IMyStalelessSessionBean myStalelessSessionBean ) {
this.myStalelessSessionBean = myStalelessSessionBean ;
}
}

Looked quite ok to me, deployment on the Weblogic server went well. So I should be ready to rock!
But, after I put something meaningful in my queue, onMessage() was not called, instead I was greeted by:

#### <> <> <> java.lang.IllegalArgumentException: argument type mismatch.
java.lang.IllegalArgumentException: argument type mismatch
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at com.bea.core.repackaged.springframework.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:121)
at com.bea.core.repackaged.springframework.jee.inject.MethodInjection.apply(MethodInjection.java:47)
at com.bea.core.repackaged.springframework.jee.inject.Jsr250Metadata.applyInjections(Jsr250Metadata.java:233)
at com.bea.core.repackaged.springframework.jee.inject.Jsr250Metadata.inject(Jsr250Metadata.java:218)
at weblogic.ejb.container.injection.EjbComponentCreatorImpl.injection(EjbComponentCreatorImpl.java:131)
at weblogic.ejb.container.injection.EjbComponentCreatorImpl.getBean(EjbComponentCreatorImpl.java:74)
at weblogic.ejb.container.manager.BaseEJBManager.createNewBeanInstance(BaseEJBManager.java:216)
at weblogic.ejb.container.manager.BaseEJBManager.allocateBean(BaseEJBManager.java:233)
at weblogic.ejb.container.manager.MessageDrivenManager.createBean(MessageDrivenManager.java:286)
at weblogic.ejb.container.pool.MessageDrivenPool.createBean(MessageDrivenPool.java:165)
at weblogic.ejb.container.pool.MessageDrivenPool.getBean(MessageDrivenPool.java:90)
at weblogic.ejb.container.internal.MDListener.execute(MDListener.java:434)
at weblogic.ejb.container.internal.MDListener.transactionalOnMessage(MDListener.java:371)
at weblogic.ejb.container.internal.MDListener.onMessage(MDListener.java:327)
at weblogic.jms.client.JMSSession.onMessage(JMSSession.java:4072)
at weblogic.jms.client.JMSSession.execute(JMSSession.java:3964)
at weblogic.jms.client.JMSSession$UseForRunnable.run(JMSSession.java:4490)
at weblogic.work.SelfTuningWorkManagerImpl$WorkAdapterImpl.run(SelfTuningWorkManagerImpl.java:464)
at weblogic.work.ExecuteThread.execute(ExecuteThread.java:200)
at weblogic.work.ExecuteThread.run(ExecuteThread.java:172)

IllegalArgumentException while calling onMessage! WTF! I was quite lost!
Tweaked the @MessageDriven-annotation and doublechecked the correct signature of onMessage. But no success!
After a while I set an ExceptionBreakpoint for IllegalArgumentException and found myself in the middle of JEE internals. Reflection all the way!

Eventually I found the culprit:
The stateless session bean I wanted to be injected seemed to be null.
Removed that code temporarily. And bang! onMessage was called. After fixing the injection everthing worked well.

But to cut a long story short:
What does an IllegalArgumentException do to help me under that circumstances. My mistake had no obvious connection to the onMessage-method.
Something more meaningful would be highly appreciated and would have saved me a lot of time.
But still it is always a little fun to me, to finally get my head around something like that ;)

Aber wie halte ich es dann mit dem “Drumherum”. Dann bräuchte ich konsequenterweise auch zwei Versionen der Menüs, des Abouts usw. Kann WordPress i18n? Gibt es dafür Plugins? Ist der Aufwand dafür gerechtfertigt? Wie aufwändig ist denn das überhaupt. Wahrscheinlich muss ich die Wahl meines Themes auch davon abhängig machen. Ich muss da noch mal in mich gehen.

I did a fresh install of wordpress, as my new provider offered me a one-click-install option. It wasn’t actually “one-click”, downloading and unzipping WordPress would have been just as fast.

There were basically two things which bothered me:

1. The installer forced me to use a custom prefix for my wordpress database tables. Usually a good thing, but the prefix could only consist of numbers and characters and especially no underscore. And it didn’t add any separator. So I ended up with tablenames like xxwp_content. Ugly, don’t you think. As I do not plan to add another wordpress installation, I could have easily stuck with wp_content but the installer did not leave that choice. This makes importing an old sql-dump harder than it should be. But I didn’t use that dump anyway ;)
2. Updates of wordpress did not work out-of-the-box. The installer forgot creating a temporary folder, so that the update process stumbled on missing files. Or my provider did not set the property pointing to temporary storage properly. Just as bad.
   So what I did was:
   • Created a temporary folder [wordpress-install-dir]/tmp
     Keep an eye on the permissions.
   • Updated wp_config.php with
     
putenv('TMPDIR='. ABSPATH .'tmp');
define('WP_TEMP_DIR', ABSPATH . 'tmp');


   After I managed to solve those issues. I actually could install the WordPress xml importer plugin and everything went fine. I just had to upload some images and I was done.

   Now I am more or less through reinstalling my former set of plugins. That was quite straightforward, except the iG:Syntax Hiliter Plugin, which did not seem to be maintained any longer. As some post rely on it, I had to manually move it from my old site. Perhaps I should look for a replacement.

   Right now I am looking out for a new theme, though iBlog looks very nice. Perhaps I’ll keep it.  It’s just that it feels more like an addon than just a style-provider.

   Perhaps this will keep me busy for some time ;) Please feel free to suggest a nice theme.

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