I’ve spent the last few hours adding a bit of javascript/araneida magick to the boinkmarks web interface. If you have javascript enabled, and your browser is supported by dojo, it’s possible to select the hosts, implementations, releases that you want in a matter of seconds (and not in 2-3 minutes). Yay!

Also, that taught me some useful lessons:

• I’m not cut out for web development. Seriously, ew.
• Parenscript is nice. But then you find out you can’t write something.innerHTML = ..., because there is no way for it to emit a variable name that consists only in part of capital letters – and javascript is case-sensitive! Argh! You can get innerHTML by using (in lisp) something.inner-h-t-m-l. (thanks to Marco Baringer and Ivan Toshov)

In other news, Postgresql = love. It’s really a joy to search for performance problems with it. The last one I weeded out was this:

When you join a small table to a big table in order to limit the number of resulting rows to ones matched in a big table, don’t use JOIN, use WHERE EXISTS.

For example, if you want smalltable’s foo column for rows that are related to those rows in bigtable that match bigtable.condition='something', don’t use

select smalltable.id, smalltable.foo
from smalltable join bigtable on bigtable.id=smalltable.id
where bigtable.condition = 'something'

, use:

select id, foo
from smalltable
where exists (select * from bigtable where bigtable.id = smalltable.id and bigtable.condition = 'something' limit 1)

(And don’t forget to keep an index on (bigtable.id, bigtable.condition)!) Rewriting sql statements like this (and using an index) gave the queries in the boinkmarks web app a speed boost of anything between 30x and 200x.

It’s still slow, but at least now I can’t do anything obvious about it anymore. (-: