Tien Chiu

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MySQL

Well, I’m slowly returning to the land of the living; I spent most of today codeine-free, meaning I actually got to do something besides drugged-out moping.  So I spent the day studying database design, MySQL, and electronics theory.  I’m doing much better with the first two than with the electronics, alas.

Following Laritza’s advice (thanks Laritza!), I have decided to go ahead and build the projects database anyway.  I am thinking of starting up a study group, and I’m thinking that this would be a good beta test – storing all the study-group projects in it and seeing if it works.  If all else fails I can keep my own projects in it rather than having to keep updating travelingtiger.com with photos, and it will be a good learning exercise.

Towards that, I read through the lone chapter on database design in Learning MySQL and have designed a relational database of sorts.  I say “of sorts” because many of the finer points (like foreign keys) are still a bit fuzzy.  I was going to run down to San Mateo to get a book on database design (to my shock, the Borders at the corner of 3rd and King, which usually has an excellent selection, had no books on the subject), but finally decided that the fuzziness wasn’t actually due to my not understanding database design, but simply from never having used a database.  There’s no way for me to tell right design from wrong design right now.  So, I decided to tackle learning MySQL first, then come back and finish the database design.

Which is where I stand right now.   I’m done with basic SQL commands and am working my way through the advanced querying section.  Hopefully that will teach me what I need to know in order to finish the database design and create my tables.  So far it isn’t difficult, but then I’ve had some (very limited) SQL experience in the past, which is helping.  Tomorrow I’m hoping to polish off the rest of the SQL section and input my database tables.

Meanwhile, my electronics knowledge continues to flail.  I simply have no intuition about any of this stuff.  I mean, I know the equations and I can do the math, but I have no more idea of what a resistor does than I did when I started.  It’s very frustrating.  The book keeps introducing concepts at lightning pace and I really don’t understand any of them.  Mike is helping somewhat, but I’m sort of at a loss.  Not sure what to do about that – I may wind up having to spend a day or two just thinking about the concepts.  I do want to understand it, I just don’t.

It reminds me of the general mental block I have around physics – up until I tinkered with a spinning wheel (well after my last formal class in physics) I had no intuitive understanding of mechanics at all.  I made it through all my physics classes on pure mathematics – I could push the equations around even though I had no idea what they actually meant.  It’s sort of like that.  I can do the calculations, it just doesn’t do me any good in terms of actual understanding.  I don’t know how to get around that.

Well, more stuff to think about tomorrow, I guess.  I might order a book with a gentler learning curve than Horowitz and Hill.

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Weaving, minor electronics, weaving database

I finally gave in and bought an electric cone winder to spare my shoulder the endless circular movements of ball-winding with very fine yarns (it took almost two hours for the fire shawl!). I promptly discovered that the ballwinder starts up too fast for fine cashmere yarns – the yarn breaks as the swift starts moving. So Mike went out and bought some parts at the hardware store, and showed me how to build a multi-speed switch using a fan control switch. It was simple, and rather neat – I thought it was really interesting! I’ve never done any electronics/electrical work so despite being very simple I learned something from it.

Unfortunately the multi-speed switch didn’t work to reduce the speed of the conewinder, so we’re going to try building something slightly more complex once the parts arrive. I’m looking forward to it – I have been vaguely interested in electronics for quite some time but have never had enough motivation to get over the initial (steep) learning curve. Perhaps this will help me get over it, or at least get a little closer.

Meanwhile, I am looking at other alternatives, like reducing the inertia of the swift. It’s been recommended that I try turning the swift sideways, which I plan to do, and/or build another swift out of an old bicycle wheel. I’d like to save that for a last resort since it would be another thing taking up VERY limited space, but I’m keeping it in mind.

I’ve also decided to build a weaving database to keep track of my drafts, as it’s difficult to describe the more complex ones in words. Ideally I would want something that allows me to enter a draft, a .jpg of that draft (WeaveIt Pro automatically generates .jpgs when a draft is saved), and one or more identifying tags (to make searching easier). Three page templates: the homepage, an individual draft page, and a search results page. The drafts themselves would continue to reside in labeled folders in the file system (this is what saves you when something goes wrong with your database) – the database would be for organizational purposes only.

This is undoubtedly overkill since I only have a few drafts, but in the back of my mind I’m thinking that, if successful, I could conceivably scale it up and provide a similar service to handweavers in general (organize your drafts via the Web). I don’t know if there would be much interest in it, but I think it might be useful for the handweaving community.

More to the point, though, I think it would provide great motivation to teach myself mySQL and PHP, which in turn would give me greater technical mastery of Web technologies I’d need to know as a Web product manager. It would also allow me to create a website that I could use as a demo for my Web design skills. So there are a lot of things that might be interesting in this project. I’ve ordered three books: one on mySQL, one on PHP, and one on web design using both. Once they arrive I plan to spend some time teaching myself to use them and then building out the site. What fun!

Finally, I have been weaving the brown and tan network drafted jacket, and have woven about 8″ so far. I may have to cut off the first 6″, though, as I had an error in my draft – I was one thread short in the repeat, resulting in a highly visible flaw in the network pattern. (This is what I get for not checking the draft before weaving. I thought I had checked it earlier, but apparently not.) So I had to insert the threads, and then I started weaving in not quite the right place, so there’s a break in the pattern. I may wind up using that section for cuffs or something where the break won’t be quite so obvious.

Anyway, it’s well started, and I hope to enjoy weaving it over the holiday weekend. Balsam Hill (the place where I’m contracting) shuts down Dec 31 and Jan 1, so I have a four-day weekend. This can mean only one thing: more weaving! (and database design, and electronics, and cycling, and…)