An Exciting Day
Here come to my most exciting part of the week - the DB lecture. But, oops, the topic changed from query optimization to revision basic stuffs, including the famous B-tree. Well, I admit for the second half of the lecture, I didn't know about that (or just know the names). Therefore, this lecture is still great! The new things I learned includes the different way of joining 2 tables, using: 1) the naive method (block nested loop); 2) the less naive method (index nested loop); 3) merge sort (external sorting); and 4) hash join. Don't be scared by the names. Actually these ideas are quite easy.
Also, thanks to Miss Mong for telling me the English name of "一筆過" - Euler Circuit. It seems that the book "Data Structures & Algorithm Analysis in C++" will be quite useful for my Rack project series (e.g. plotter, scanner, typewritter, fax, etc).
p.s. Just to remind myself, scanner can use RLE (run length encoding) to save space.