Thursday, 3rd November 2005
Back from the depths
I haven't been blogging. Again. But here are some of the things that I would have blogged about:
Last Friday, the bus from uni hurtled its way straight past not one, not two, not three, but four consecutive bus stops where people wanted to get off, and who were indicating this by a) filling the aisle by trying to stand next to the door, and b) repeatedly (and ever-more-viciously) pressing the audibly beepy Stop button whilst the driver was all the while ignoring every one of us. (And unfortunately, we were all too English to ask him what on earth he thought he was doing.)
Net result: I missed my connecting bus completely as I was dumped over a mile up the road from where I wanted to be (I wanted the first bus stop that the driver had ignored), had to get a substitute bus that went vaguely in the right direction (the driver of which completely ignored my running alongside the bus and waving for him to stop, and then had to stop two seconds later anyway because there was a woman with pushchair whom he hadn't let off the first time. But anyway) and then walked the last 15-20 minutes, all the while cold and also With Cold.
Warwick Uni has blogs system. Whilst many of the postings are of the "what I did last night" variety (due to the very insular, LiveJournal-type community), I'm currently still trying to overcome my shock at the blogger seriously, if unintelligently, arguing for forced abortions and jail sentences for under-age pregnant girls. Even so, it wouldn't have stood out in my mind quite so much had I not just read another Warwick post pondering whether or not "chavs" should be allowed to vote.
I've been getting deluged with information about careers and recruitment fairs and internships and am now starting to vaguely wonder if I should be doing work experience over the summer.
Although most of the deadlines are in the next 2-4 weeks.
I've been getting distracted from my courseworks by a pet Python project (or rather, I started a Python project in an attempt to avoid coursework).
Unfortunately this only took two days, so I'm back to coursework again.
(although I do still have to convert it from a simple script into a CGI script callable from a webpage)
(and try to improve the error reporting)
(and then announce it to the world)
I've been wondering why our database coursework specifies that we must not use NULL values.
Especially since this means that all of the optional fields in the spec have to be farmed out into completely separate TABLES.
I'm also wondering if I'll ever grasp concurrent programming, but that's a by the by.
I note that my cooking, whilst not great, is at least better than Anna's.
(But only because I follow a printed recipe for complicated meals.)
And I wonder if I'll ever ever learn to do all the washing and ironing at the weekend, without leaving dry pre-iron clothes hanging up all week.
I've also been saving the world a bit. But only at night.
Comments
Read it all.
"Finished, Miss!"
Well done. Have a gold star :-)
I never like the 'insularity' of warwick blogs either...which is why I rushed out back to a proper website as soon as I could.
The use of NULL is a first-rate pain and its use should be avoided at all costs.
Are you wanting to use it for, for example, PregnancyDate in an employee record where the employee is male? If so there are two options: a) normalisation - remove the offending fields to separate tables; b) ignore the value if employee is male.
I tend to use the latter and set the PregnancyDate to zero.
The assignment is to do with a directory of companies, and so one of the tables holds details for the company - name, address, etc. One of the optional fields is email address, so it's not quite as simplistic as your example - there's no way to predict whether or not a company will have provided an email address.
Could you tell me why it's better to use zero instead of NULL? I really do want to know, and I can't see that there's any difference between the two.
O.O The bus driver sounds weird. But just thank your gods that you're not in Malaysia - in my neighbourhood you see 1 bus every 2 hours. And that's the bus headed downtown.
If they didn't supply an email address, let the field contain an empty string.
NULL means "unknown value". Being hugely pedantic, the "correct" value might be NULL meaning that the value is unknown or it might be empty indicating the lack of an email address. In other words, maybe they have an address but you don't know what it is and maybe they don't have an address.
Being practical, you mostly don't care which interpretation is strictly correct, you just want to email those for whom you have addresses.
SELECT * WHERE email <> "" is so much more convenient than
SELECT * WHERE NOTISNULL(email) and (email <> "")
Hmm, interesting. I'll still go the normalisation route, since the finished assignment won't have any populated tables or anything - we're basically just handing in the CREATE TABLE statements, and drawing E/R diagrams etc.
I'll bear what you've said in mind for the future though, thanks.
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