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Exchanging PostgreSQL for Oracle

I have a client who was building some commercial software on top of PostgreSQL. This plans to be a fairly high volume site, 1.8 million views/hour 500 hits a second. Most of the software seemed to work just fine, but they had some issues with Postgres. Specifically, the backup was failing and we couldn’t figure out why. Then, a few days ago, we saw this message:

ERROR: could not access status of transaction 1936028719
DETAIL: could not open file “/usr/local/postgres/data/pg_clog/0836”: No such file or directory

After a bit of searching, I saw two threads suggesting fixes, which ranged from deleting the offending row to recreating the entire database.

I suggested these to my client, and he thought about it for a couple of days and came up with a solution not suggested on these threads: move to Oracle. Oracle, whose licensing and pricing has been famously opaque, now has a pricing list available online, with prices for the Standard Edition One and Enterprise Edition versions of their database, as well as other software they sell. And my client decided that he could stomach paying for Oracle, given:

1. The prices aren’t too bad.
2. The amount of support and knowledgeable folks available for Oracle dwarfs the community of Postgres.
3. He just wants something to work. The value add of his company is in his service, not in the back end database (as long as it runs).

I can’t fault him for his decision. PostgreSQL is full featured, was probably responsible for Oracle becoming more transparent and reasonable in pricing, and I’ve used it in the past, but he’d had enough. It’s the same reason many folks have Macs or Windows when there is linux, which is a free tank that is “… invulnerable, and can drive across rocks and swamps at ninety miles an hour while getting a hundred miles to the gallon!”.

I’ll let you know how the migration goes.

Oracle Technology | moore |

Breaking WEP: a Flash Presentation

About two years ago, I wrote about how to secure your wireless network by changing your router password, your SSID, and turning on WEP. Regarding WEP, I wrote:

This is a 128 bit encryption protocol. It’s not supposed to be very secure, but, as my friend said, it’s like locking your car–a thief can still get in, but it might make it hard enough to not be worth their while.

Now, some folks have created a flash movie showing just how easy it is to break WEP. Interesting to watch, and has a thumping soundtrack to boot.

Via Sex, Drugs, and Unix.

Technology | moore |

Blogging and Legal Issues

Any new technology needs to fit into existing societal infrastructures, whether it’s the printing press or the closed circuit TV system. Blogging is no different. I sometimes blog about what I get paid to work on, but always check with my employer first to make sure they’re comfortable with it. Since I’m a developer, it’s often general solutions to problems, and if need be, I omit any identifying information. Some folks take it farther..

Now, our good friends at the EFF have produced a legal guide for bloggers, which looks to be very useful, but is aimed only at those who live in the United States of America.

Technology | moore |

Search engine hits: a logfile analysis

I get most of my website hits on two posts: Yahoo Mail Problems and Using JAAS for Authentication and Authorization. It’s common knowledge that if your business “does not rank in the top 20 spots on the major search engines, you might as well be in the millionth ranking spot”, but that’s apparently not strictly true for content. I looked at my webserver logs over a 42 hours stretch, when I got 125 hits from search engines, and looked at the start parameter, which generally indicates what page the results were on (0 is typically the first 10 results, 10 is the second 10, etc).

Here’s the graph of my results:

I have to admit I’m suprised by the number of hits beyond the first 20 results (columns 0 and 1)… 71.2% were from the first two pages, but that measn that 28.8% were from deeper in the search engine results. And someone went all the way to page 20–looking for a “servlet free mock exam” if you must know.

Interesting, for sure. Not that I’m claiming this is a long tail.

Technology | moore |

Useful Tools: wget

I remember writing a spidering program to verify url correctness, about six years ago. I used lwp and wrote threads and all kinds of good stuff. It marked me. Used to be, whenever I want to grab a chunk of html from a server, I scratch out a 30 line perl script. Now I have an alternative. wget (or should it be GNU wget?) is a fantastic way to spider sites. In fact, I just grabbed all the mp3s available here with this command:

wget -r -w 5 --random-wait http://www.turtleserviceslimited.org/jukebox.htm

The random wait is in there because I didn’t want to overwhelm their servers or get locked out due to repeated, obviously nonhuman resource requests. Pretty cool little tool that can do a lot, as you can see from the options list.

Technology Useful Tools | moore |

IVR UI Guidelines

I was just complaining today to some friends that IVR systems (interactive voice recognition, or, the annoying female voice who ‘answers’ the phone and tries to direct you to the correct department when you call your credit card company) need some guidelines because it seems like every system does things just a little bit differently–enough to annoy the heck out of me. Well, lo and behold, google knows. Here is a paper on the topic and here’s a coffee talk on the topic by a former coworker (today must be a day for references to former coworkers).

Some of my frustrations with IVR systems are due to the very market forces that drive companies to use them (making it hard to reach an operator helps when trying to cut labor costs) and some are due to limitations on audio as an information conveyance (typically, reading is quicker than listening).

Updated Sep 12 2006 with correct link and tags.
[tags]IVR, interactive voice recognition, inovdesigns[/tags]

Technology | moore |

New tech comic

Jut got an email from an old coworker who used to do some pretty great comic strips. (Nothing nationally syndicated that I know of.) He’s started a new one, Bug Bash, that is ‘updated weekly, technology-focused, and based loosely on my experiences at “a large northwest software company.” ‘

Take a look…

Technology | moore |

Installing eRoom 7 on Windows XP Pro

This is a quick doc explaining how to install eRoom 7 on Windows XP Professional. It assumes that Windows XP Pro is installed, and you have the eRoom 7 setup program downloaded. This is based on the events of last week, but I believe I remembered everything.

1. Install IIS.

2. Make sure the install account has the ‘Act As Part Of The Operating System’ privilege. Do this by opening up your control panel (changing to the classic view if need be), double clicking Adminstrative Tools, then Local Security Policy, then expanding the Local Policies node, then clicking the User Rights Assignment node. Double click on ‘Act as part of the operating system’ (it’s the 2nd entry on my list) and add the user that will be installing eRoom.

3. Restart.

4. Run the eRoom setup program. At the end, you’ll get this message:

Exception number 0x80040707
Description: Dll function call crashed ISRT._DoSprintf

5. Re-register all your eRoom dlls by opening up a cmd window, cding to C:\Program Files\eRoom\eRoom Server\ and running

regsvr32.exe [dllname]

for each dll in that directory.

6. Run the eRoom MMC plugin: Start Menu, Run, “C:\Program Files\eRoom\eRoom Server\ERSAdmin.msc”

You should then be able to create a site via this screen.

Technology | moore |