Friday, 12 June 2009


When I first heard about twitter I mostly ignored it like I ignored Instant Message. I have better things to do with my time than watch what other people are doing. IM always seemed to be just another source of interruptions. I shut down my email much of the time and check it when I'm not doing something more important. If people need to contact me urgently they can phone (unless I have turned my phone off... which I do).

Actually I even filter emails into ones that are addressed to me and ones that are only CC'd to me. The CC ones go into a different folder. I only check those when I am bored. Given some of the people I work with only seem to know about the 'reply all' button this saves me a lot of time. It is also quite nice to just clear that folder, knowing there is never anything important in it.

But back to Twitter. I work in a team spread over different locations. When time gets tight there are a lot of 'where are you up to?' emails from project managers. They like to have conference calls too, not quick ones either. It gobbles up time like crazy. So I started using twitter. If they want to find out what I'm up to they can check that. Saves a lot of back and forth.

Even more useful, I RSS my own Twitter into my email (this is simple enough on Thunderbird, probably on other email clients too). It seems narcissistic, but this gives me a simple way to track what I am doing. It comes in handy for filling out timesheets. The Twitter page itself is not very clear as to what time an entry was made, but the email always has a timestamp. It doesn't have to be dead accurate.

I could write a small application to do this, but it wouldn't tell my project manager what I am doing. Twitter manages both. I like the succinct format, just a few characters to say what I need and move on. Works for me.

Friday, 5 June 2009

Oracle XE

There are lots of things I don't like about Oracle, but some of them are historical. Back in the '90s I wrestled with upgrading from something like Oracle 6 to 7 on an Ultrix box for a week. It was just an upgrade on a dev machine and it was far more complicated than it should have been. They're better than that now. Even so I grit my teeth and worry whenever I have to do anything that looks like installing Oracle.

For developers it always seemed such overkill that to install a database you end up with an application server and a bunch of other stuff. I just wanted a database. I have a different application server (and, more to the point, my customers have a different application server). So I have to have two of them running on my dev machine.

Enter Oracle XE. They have done something good here. It is easy to install, free to developers and is just a database with the overhead of a database not a big fat application server. It runs fine on Windows and it runs fine on Linux (Ubuntu anyway, where I've tried it). In both cases the install is clean and simple. Go Oracle.

It doesn't allow you to have multiple databases, but it does allow you to have multiple schemas. I tend to work on multiple projcts at once which really need multiple databases (the projects typically have the same schema names but different data and slightly different definitions). There was a time where this would have been a pain but the support folks in my day job have got their act together and built decent db scripts for each project. So when I switch I can run the script and I'm done. There's an overhead there, but it is less of an overhead than running full Oracle.

With those issues sorted Oracle is a good development db. Though these days I like to hide everything behind Hibernate to keep portable.

Tuesday, 2 June 2009

Ubuntu Printing

I'm migrating my laptop (Dell Insprion 9400) to Ubuntu 'Hardy Heron" 8.04.

Tonight I tried hooking up to the printer, which is an HP 3420 connected through a TrendNet TE100-P1U print server, and that is plugged into a wireless hub. My laptop talks to the hub just fine already. The internet connection is on the hub as well.

Setting up the printer is fairly simple. On windows I had the following specified:
port name: IP_x192.168.123.10
printer name or IP Address:
Queue name: U1

For Ubuntu I found I just had to pick:
New Printer
LPD/LPR Host or Printer
Give it a host name ( in my case). This is a fixed address, I don't think you'd want DHCP addresses for your print server.
Ignore the Queue requested
Specify the printer type (HP then 3420 in my case)
...and then the fun starts. Well no. It prints blank pages.
It sounds like it is printing, looks like it is printing but what I get is a blank sheet of paper.

I found a few references on this. The most useful was here but it is kind of terse. The link he gives there (http://localhost:631) gets you browsing the CUPS UI. It isn't all that clear what you have to do. However I had not seen the CUPS UI before. It is probably a nicer way to control the printers than the UI on the desktop.

What I did was pick 'modify printer' and work through the wizard sequence to the page shown in the image. By default the other option for HP 3420 was picked and the solution was to pick the one I show in the pic. Then it all came right. The test page printed etc.

The underlying issue seems to be that by default the printer uses only the coloured inks and never the black ink. Like lots of people our coloured inks are empty and we only use the black one, so nothing printed.

From reading several other entries this is not specific to the 3420, or even HP printers. So your fix may vary a little from mine.