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| 2005/7/26-28 [Computer/SW/Database] UID:38823 Activity:nil |
7/26 Hello SQL experts, I have two tables, A and B. A has 1/2 million
rows and B has 2 million rows. The relationship is A.id=B.A_id.
Whenever I have something like:
SELECT A.id, AVG(B.val) FROM A,B WHERE A.date<'2008-01-01' AND
A.id=B.A_id GROUP BY A.id;
It takes about 20-30 seconds. Anyone know why? I've already
indexed all the ids.
\_ Do you have an index on A.date?
\_ Yes I do. I found out something new. I did a
SELECT COUNT(*) FROM ... <rest is the same here>
and I got 63 million rows. I'm guessing something
is really screwy here, do you have a clue?
How about INNER JOIN, is that faster? How do I use it?
\_ The syntax you gave is an inner join by default in most
databases. In mysql or pgsql at least, try adding "explain"
to the beginning of your select. This will tell you which
keys it's trying to use, how many rows each step gets
filtered down to, etc. --dbushong
\_ Hello I'm the op. I've reduced my problem to the following.
Say I have 4 tables, A, B, C, and D. When I do a
SELECT COUNT(*) and I join A and B, it is pretty fast.
When I join A, B, and C, it is twice as slow. And when
I join all of them, it is FOUR times as slow. I've made
sure that all the joint columns are INDEXed. Why is this
happening?
\_ You're specifying 3 join conditions, right? You have non-unique
indexes on the foreign keys and unique primary keys?
\_ Thanks Dave. Basically, column A.id is unique, column B.id
is not unique. A.id maps to B.id. Similarly, C.id is not
not unique, but also maps to B.id. Is this the reason?
I need a one to many mapping and I don't know how to get
around it.
\_ if you're using mysql, mysql can only use one index per table.
if you're joining on multiple columns, that could be your problem |
| 2005/7/26 [Reference/Religion] UID:38824 Activity:nil |
7/25 I have a novel approach to finding and getting rid of suicide
bombers, please tell me what you think, and if it's doable.
You [government] hire a bunch of patriotic Muslims to recruit
people who are anti-government and want to blow themselves up.
You give them backbacks filled with dud-bombs that do nothing
but give off smoke. You then arrest them while they are smoking
in the vicinity of a lot of people. What do you think?
\_ That's nice here you can have a cookie before naptime.
\_ patriotic muslims == infidel
\_ That's similar to how we trick drug dealers. |
| 2005/7/26 [Computer/SW/Security] UID:38825 Activity:high |
7/26 Doing the jobs American's won't do...
Mexican accused of leading document-fraud ring - Millions
of phony IDs for illegal aliens
http://www.freerepublic.com/focus/f-news/1450601/posts
\_ Yay, freeper is back! --freeper #1 fan
\_ And Freeper doesn't know how use an apostrophe! What a
dolt.
\_ Nice way to duck the issue raised with a weak personal attack.
I don't read freeperlinks or like freeperguy but you're
making yourself look more stupid than freeperguy. Either
respond intelligently, putting him in his place, or ignore it
if you have nothing worth saying.
\_ What's the issue to duck? Freeperguy hates immigrants.
This has been long established. There really isn't much
to do except make fun of him.
<<<<<<< /home/sgi/dcs/tms
\_ I'm not ducking anything. I didn't even read the article,
sounds boring. He didn't even make a point.
=======
\_ You haven't made fun of him. You've made yourself
look petty, stupid, and childish, assuming it was you
getting personal above. Just ignore it. Why can't
you see you're only encouraging it?
\_ FWIW, I wasn't the one making fun of freeperguy's
grammatical problems. --pp
\_ And he's getting incredibly good at hiding his identity
>>>>>>> /etc/motd.public |
| 2005/7/26-27 [Academia/GradSchool] UID:38826 Activity:nil |
7/26 Spam filtering for grad students:
http://www.phdcomics.com/comics/comics.php |
| 2005/7/26 [Transportation/PublicTransit] UID:38827 Activity:kinda low |
7/26 Spare the Air Day.
\_ So claimed the crazy Microsoft bicycle guy standing on the caltrain
platform. Fuck you crazy MS bicycle guy, maybe if you stopped
yelling about how people bungee their bikes you'd have some
credibility. -- bought a ticket, proud to support caltrain
\_ Caltrain rules, BART drools. |
| 2005/7/26 [Politics/Foreign/Asia, Politics/Foreign/Asia/Others] UID:38828 Activity:moderate |
7/26 So rich Korean/Chinese/Taiwanese/Singapore single lonely dude all
mail orders pretty Vietnamese girls, what about Vietnamese
dude?? What the hell do they do? ;)
\_ Mail-order from Laos?
\_ Please don't lump Singapore with males chauvinist countries like
USA, China, Korea, Taiwan, Japan, etc. Singapore doesn't have a sex
ratio problem:
at birth: 1.08 male(s)/female
under 15 years: 1.07 male(s)/female
15-64 years: 0.95 male(s)/female
65 years and over: 0.79 male(s)/female
total population: 0.96 male(s)/female (2005 est.)
\_ Many boys die while growing up?
\_ that's the same everywhere. go check at:
http://www.indexmundi.com -> country -> people -> sex ratio
\_ Men have higher mortality for a bunch of reasons, military
service, more likely to be involved in violent crime, more
likely to take stupid risks for fun, etc etc.
\_ more likely to write on the motd |
| 2005/7/26-27 [Science/Space, Politics/Foreign/MiddleEast/Israel] UID:38829 Activity:nil |
7/26 So what do ppl think re: NASA?
1) Stick with shuttle program?
2) Scrap the shuttle, move to the next type of launch vehicle
3) We should build a moon base
4) Manned-Mars Ho!
5) IIS - make it an orbital station for whatever launch vehicle
we choose for (2).
\_ Can't do #3 or #4 without #2. #1 is stupid. Therefore, #2.
\_ Agreed. -mice
\_ We have to go ask our asian lenders for more lunch money
because we already spent our allowance for the next 5
centuries on the Iraq invasion.
\_ Nah -- we just allocate some of that money for starting
a war with our debtors, then after bombing them back
into the Third Age, we rebuild their country with
Americanized values and declare them either the 51st
state, or a 'Protectorate' with symbolic representation
in the senate.
\_ Scrap NASA and start over, imo. This gold-plating and closed
competition between Lockheed and Boeing has to stop. -- ilyas
\- A nice line I heard was "pentagon procurement is one of the
last bastions of stalinism". where in russia are you from?
\_ Odessa. Interestingly, Odessa is considered the 'city of
humor' in Russia. It was a largely jewish city, and there
is a 'certain culture' to it. It's a lot like a russian
version of San Francisco, I would say. -- ilyas
\_ here's some pics: http://www.sergeyv.com --!ilyas
\_ So let me get this right. You're not a Jew, but you're
almost a Jew because of exposure with Jews? If that's
the case, I will start respecting you a bit.
-not a jew but totally worship them
\_ I am not russian either. I have no nation. You would
be interested to know that during the formation of the
state of Israel, they considered anybody who considered
themselves a Jew to be a Jew (for the purposes of
immigration). -- ilyas
\_ In other words, you too can be a Jew, Jew
worshipper guy! |
| 2005/7/26-29 [Transportation/Car, Transportation/Car/RoadHogs] UID:38830 Activity:high |
7/26 To the free market troll complaining about how the government shouldn't
fund an R&D project into better roads. Have you any idea how many
commercial(read: free market) companies owe their technology to basic
science funded by the government? Hell. If not for that, you wouldn't
even have a career.
\_ I am probably the guy you think is the free market troll. You
didn't read my posts carefully enough. I totally support government
funding of R&D of all kinds, government funding of roads, and
government funding of public mass transit. I just loathe car
culture, and think that our present system is not based on either
a free market or government support of rational transit, but rather
is based on whoring out the country for the car companies and
suburban developers. You may address me as "anti-car troll" if
you want to be accurate.
\_ "whoring out the country for the car companies..."? Did you
just graduate from highschool? That's the sort of
demagoguery I'd expect from a freshman or sophomore with all the
accompanying idealisitic 'Im gonna change the *world*!!!!'
demagoguery I'd expect from a freshman or sophomore will all the
accompanying idealisitic 'Im-a gonna change the *world*!!!!'
zeal.
\_ I'm not lafe but I just want to say that when I was in
college I was full of optimism and energy because I
felt that I could do a lot to make this world better.
Now that I'm in my 30s, working 9-5... I feel that
there isn't much I can really do to drastically
change the world. You just live life the way life
wants you to live. Does anyone feel similar?
\_ Not at all; I'm not a victim. -pp
\_ No. Try to be a good guy, debate eloquently, stand by
your convictions. What's so hard about that? Make what
little difference you can, and enjoy watching the morons
around you send the world to hell in a handbasket. And
regarding the comment below, Europe has good public
transit, but the cities are also generally a lot more
densely populated. -John
\_ I do try to live my life modestly and reasonably, but
I've concluded that the world doesn't want to be made
better. See GC's comments on "Paradox of Our Time"
http://www.georgecarlin.com/home/dontblame.html
\_ So, your alternative to car culture...?
\_ See Europe. Walkable/bikable cities, subsidized mass
transit. High gas taxes to discourage use of the
automobile. Discourage sprawl.
\_ Europe's big cities are very densely populated. The
rest of Europe uses cars just like here.
\_ Even smaller European cities have very usable
public transportation (better than, say, SF/Oak).
And even less densly populated regions are well
served by public transport. I was able to get
from the door of my apartment to standing on a
glacier (in another country no less!) solely
though public transport (well, and some walking).
\_ So you suggest a *massive* rebuilding of our
entire culture where we literally rip up everything
now in place, and rebuild everyone's home, work,
the transit system, utilities, everything, so you
don't have to live in car culture? Seriously, I've
never said this to anyone before but if you're that
upset you should just move to another country that
suits you better. Living here will just keep you
bitter and angry. Note, I don't say 'make'. You
are already bitter and angry to a ridiculous degree
over something that will *never* be anything like
the way you want.
\_ Ok, take a couple of deep breaths and re-read
my post. You will see that I do not suggest
anything; I just offered a counter statement
and supporting anecdote to the post before
me. Physician, heal thyself. -- pp
\_ Ok, so you advocate nothing when the original
point of this sub-thread was "What is your
alternative to car culture?". To say that
you advocate nothing when you're really
advocating European style transit which would
require a massive and near complete
rebuilding of society is pure intellectual
dishonesty. To then turn around and say the
fault is mine and that you're this calm and
together person while I'm some nut case is
pure dishonesty. Care to actually discuss
the issue instead of nutting around?
\_ I predict that within 10 years gasoline
will be $10/gallon and the rebulding of
America into a denser and more sustainable
fashion will begin happening all on its
own. And yes, you are the one that sounds
angry and bitter and extreme here. !-pp
\_ It isn't possible to be angry/bitter
about something I don't care about.
Questioning someone who questions the
status quo is hardly extreme. Now
you're just being silly. Re-read and
try again. I predict that whatever
happens, if you predict enough random
things you'll eventually be right
about some of them.
\_ Are you familiar with the Peak Oil
hypothesis? I am not predicting a
"random" thing, I am subscribing
to a theory that already has quite
a bit of evidence to back it up.
\_ I've read a lot on both sides of
the peak oil hypothesis. I'm
still undecided. Thinking about
it now, no, I don't think oil
will ever get to $10/gallon in
today's currency because there
are other energy sources that
cost less than that, but more
than the current price. Oil
can exceed those numbers due to
current inertial reliance, but
not to infinity and I don't
believe to $10/g. I still
remember all the scare movies
in the 70s telling us how by
the mid 80s the world would be
completely out of oil. I'm not
easily convinced that state of
affairs is always ~10 years away.
\_ A while ago I saw a seaman's
handbook written in the 70's
that quite sincerely stated
that sail might well be comming
back in the near future so
merchant seamen should learn
sailing related skills.
\_ So I did some research and
I agree that because of coal
to gasoline processes, gas
will probably not hit $10
anytime soon. I think $5 is
very likely though.
\_ I wouldn't say that smaller cities have better
public transport than SF does. There is, for
instance, no subway. You might be able to get
on a bus, but you can do that here, too, if
you don't mind a 3 hour trip to go 20 miles.
My point was that Europe, outside of the dense
cities, is also a car culture. Try driving
from Paris to the Mediterranean during the
summer. The roads are packed. Mostly the old and
the poor use public transport, just like here,
unless they live in a big city (like our NYC).
Plenty of Europeans own cars and use them to,
say, go to Wal-Mart.
\_ Yeah, traffic here is horrible, as bad as
LA -- I don't deny that (though the highways
are also much narrower). But at the same time,
of the 12 people I work with closely, every
single one takes public transportation to work.
of the 12 people I work with closely, not a
single one drives to work.
I live in a town that isn't that much larger
than Des Moines and it has functioning public
transportation. You are right, there is no
subway here, but there are trams. However,
to go 20 mi, I wouldn't use either -- I'd
take a train and, if well timed, it should take
about 40 minutes door-to-door with public
transportation (less if I biked to the train
station, which I probably would). It is un-
realistic to expect the US to become this way
overnight, and there are some inherent
differences between Europe and the US that
may make it hard to implement such a system,
but the difference isn't just an "economy-
of-scale" effect from large cities -- many
smaller European cities have well functioning
public transportation.
\_ When I was on vacation, I took trains everywhere.
The train from Nice to Paris took about seven
hours. I could have done it in a bullet train
in about four, but I wanted to do it overnight
and get a sleeper. The people I shared my
cabin with certainly were not poor.
\_ Trains will get you to a city, but are
not helpful to get you to a particular
destination. I can fly from LA to SF
for cheap, so I guess flying is better
than public transportation. Why would
someone take a train to Nice if they
could fly?
\_ Easy -- it takes an hour to get from
your house to the airport, where you
need to arrive an hour in advance.
The flight takes an hour, and it
takes another hour to get from the
airport to the city center. So, even
though the flight is only 1 hr, you
are in transit for 4 hours. When
factoring in the time it takes to get
to the train station, it probably
takes a little bit longer, but the
experience is much more pleasant.
\_ The solution is obviously to build
more airports so that it won't
take 2 hours there/back.
\_ Or more train stations with
bullet trains.
\_ You can take a cab or local transit
or even rent a car once you get there.
Flying is a sort of mass transit, actually.
How is it fundamentally different than
Greyhound??
\_ Same as in Hong Kong and around the Tokyo area. Many
people have nice cars, but they don't drive them
everyday.
\_ In Tokyo, you don't have to. In NYC, you don't
have to. It's unreasonable to expect the same
level of public transit in, say, Des Moines.
\_ I've never been to Tokyo, but the idea that you can
get around NYC with just public transit is simply
wrong. Even if you want to think that Manhattan =
NYC, this still isn't so and the incredible number
of cabs and other private driving services should
make this clear. If public transit was so great
and workable in NYC, there wouldn't be so many
cabbies. A cab is *waaaay* more expensive than
public transit, btw.
\_ There are tons of cabbies in Tokyo, and
Seoul as well. Seoul has great public
transit, but that doesn't mean you don't
sometimes need a car, and therefore a cab.
There are even some cases where a cab is
cheaper than public transit. Quite a few
in fact. -jrleek
\_ Absolutely. I don't think many people are
arguing for getting rid of all cars. Taking
public transit for an IKEA shopping trip
is probably impractical, and there are
plenty of remote regions that don't need
to be served by public transit. The aim
of car alternatives should not be to
replace cars in all situations, just
common ones (people don't go on IKEA
shopping sprees every day, people do
go to work every day).
\_ in other countries ikea provides
very good delivery service for
big items. for small items, just
call a cab. still don't need car.
\_ I have been to NYC dozens of times and have
never taken a cab. The transit system does
everything I have ever wanted it to do in
NYC. Have you ever even been there before?
\_ yes, i was born and raised there. how many
times did you visit our fine city?
\_ dozens. I don't know the exact number.
\_ Someone needs to ilyas this post.
\_ To verbify is the American way... urr, I mean it's to
Americanize.
\_ I think that guy didn't have a problem with government funding R&D
projects in general. He only had a problem with funding R&D
projects into better roads.
an way... urr, I mean it's to
Americanize.
\_ I think that guy didn't have a problem with government funding R&D
projects in general. He only had a problem with funding R&D
projects into better roads. |
| 2005/7/26-28 [Computer/HW/IO] UID:38831 Activity:nil |
7/27 anyone want to sell me a used kinesis keyboard? email
me - danh |
| 2005/7/26-8/19 [Computer/SW/Unix, Computer/HW/Drives] UID:38832 Activity:nil |
7/26 Root will be moving office home directories to the new file server
this Friday, and soda home directories this Saturday. Expect
downtime, I've gotta rsync off of TDA: the slowest disk on the face
of the earth. - jvarga
\_ Home dir move postponed pending some serious issues with keg and
new soda. - jvarga
\_ Home dir move complete. |
| 2005/7/26-28 [Academia/Berkeley/CSUA, Academia/Berkeley/CSUA/Motd] UID:38833 Activity:moderate 57%like:38555 53%like:38796 |
7/26 More administrativa including upcoming downtime. Read the official
motd you hozers. - jvarga
\_ jvarga et al -- what sorts of booze? I'd be glad to donate some
cash for a discretionary entertainment fund for our hardworking
rootish adminy volunteer people.... -mice
\_ I dunno. I don't drink alcohol at all, and njh is going to be
out of town. Chances are that I will be making these changes
in my underwear from the comfort of my home. - jvarga
\_ You shouldn't request booze if you don't want any. Your
punishment to drink the vodka in the filing cabinet! ...
No, I guess being the CSUA sysadmin is punishment
enough... :P
\_ I usually request booze to make the rest of root easier
to work with. - jvarga
\_ Back in my day, we just used the bat for that. When
twohey wasn't busy using it on his project partners,
that is...
\_ I think the last time root types assembled with alcohol, we had
wine. Perhaps a dessert wine, like a port.
\_ fag.
\_ I don't get it. What would you prefer?
\_ I think ya do, Trebek! I think ya do!
\_ Buckfutter!!1!
\_ It's a joke, son.
\_ jvarga - are you going to be in Berkeley next tuesday afternoon?
I'd like to thank you (and give you a donation for the csua) in
person. --ranga
\_ I get out of classes at 4pm, after which I'll likely be in the
office slamming my head against things after the home dir move.
- jvarga
\_ stalker alert!
\_ ranga I'm poor, can you please treat me to Fondue Fred
tomorrow? -poor student
\_ poor student: so presumably you have some free time and
talent to donate. do do anything for the CSUA or are
talent to donate. do you do anything for the CSUA or are
you just a leech?
\_ he's a poor student precisely because he has no free
time and/or talent with which to make money.
\_ I'm a poor student because I spend all my time doing
stuff for the CSUA rather than getting a real job.
- jvarga
\_ Any idea when /ftp will be up again? Thx. |
| 2005/7/26-28 [Computer/HW/Drives] UID:38834 Activity:nil |
7/26 What is the maxium hard disk size with LBA48? Where can
I find a LBA48 spec? I've looked everywhere.
\_ The upper limit to LBA48 is somewhere on the order of 144
petabytes, or 144000 million gigs. In other words, there's no
need to every worry about geometry sized limitations according
to the spec.
\_ No one will ever need more than 64k of RAM.
\_ Well, actually, you might be right. The complete
archived internet contains about 1 Petabyte of data,
so on a simple linear extrapolation an LBA48 drive that
contains a 144 petabyte drive the would run out of disk
space in about 150 years. I'm not quite sure if the
web is expanding or not or if that expansion is linear
or geometric, I would assume the latter, so it may only
last for say 25 years.
\_ If we're talking about the same thing, it's 2^37 bytes, AKA 128GiB
aka 137GB.
\_ No, you're wrong. |
| 2005/7/26-29 [Consumer/Camera, Computer/HW/Laptop] UID:38835 Activity:low |
7/26 What are the pros and cons of Compact Flash versus Secure Digital
for a camera?
\_ Please add to the list:
Pro for CF:
1. harder to break physically
2. harder to lose
Pro for SD:
1. smaller form factor
\_ You can get a Firewire CF reader from Lexar and SanDisk but
afaik no one makes a FW SD card reader.
I've tried a FW and a USB2 CF reader and the FW reader is
noticably faster.
\- my understanding is cameras are moving in the direction of SD
but it seems to me there isnt much of a choice today, meaning
you can choose whether to get the same body with CF or SD.
and i wouldnt think not having SD is a reason to rule out
a body or somethign especially important to wait for [as might
be a full size sensor etc. with somethign that small, who cares
about size [assuming it is a decent sized camera].
\_ Really? A friend who knows pro photographers said that SD
isn't taken seriously because it's too fragile. It's thin
isn't taken seriously because it's too fragile. It's small
and the "pins" are exposed. On the other hand, perhaps
amateur photography has moved toward SD; PDAs certainly have.
\_ There are loads of multi-card readers (CF, SD, Memory Stick, etc)
around. I have one, I can look up the maker if you want. -John
\- the author of http://tinyurl.com/8s9ky made the claim
about moving CF -> SD. i find this peculiar ... i'd think
it would be easier to make say a 8gb card in the CF form
factor than SD, and i think people want space and speed
over saving 1oz. anyway, just passing along a claim.
\_ Is one or the other more reliable/longer lasting?
\_ As above mentioned, size is a key factor. I think for consumer
digicams, SD is the way to go. Last I checked, CF was still quite
a bit faster than SD. If that's still the case, CF definitely
belongs in prosumer and upper level cameras. Oh, and another
advantage for CF is that it's just a PCMCIA on a smaller form.
So compatibility with laptops(with pcmcia adapter) will be better.
\_ new laptops and pcs seems to have card readers built in. |
| 2005/7/26-28 [Computer/SW/Mail] UID:38836 Activity:nil |
7/26 What's a graphical mail reader for unix that lets
me specify multiple SMTP servers for sending email?
For instance for GMAIL i want to use <DEAD>smtp.gmail.com<DEAD> .
for work I want to use <DEAD>smtp.work.com<DEAD> . I can sort of do
it in Thunderbird if I manually change the SMTP server
every time I send mail from certain locations. - danh
\_ Mozilla. Under Mail & Newsgroup settings -> SMTP Servers ->
Advanced. Probably Tbird as well. -John |
| 2005/7/26-27 [Recreation/Humor, Academia/GradSchool] UID:38838 Activity:nil |
7/26 Was it a Douglas Adams book that had an offhand joke about the
Committee For The Study Of The Exceedingly Obvious?
http://www.thedartmouth.com/article.php?aid=2005071201040 |
| 2005/7/26-31 [Computer/SW/OS/OsX] UID:38839 Activity:nil |
7/26 My wife uses NJStar on Windoze, but is thinking of changing to the
Mac;however, entering text in traditional chinese is a pain. Is
there an input method for OS X that is similar to that used by
NJStar? tia.
\_ yes. OSX comes w/ builtin language support for typing chinese.
i know you can do the pinyin method of input. i'm know there are
others.
\_ thx for the reply. the default input method seemed very slow
and painful on my G5 in comparison to NJStar on windows using
pinyin. However, using the translation feature from simple to
traditional wasn't too awful, though, we couldn't do the whole
document at once. Any plugins that are faster and/or more
intuitive than the defaults? TIA.
\_ i only know of the defaults. the input seems relatively
speedy to me. NJStar is definitely more polished, but i
haven't had any problems inputing chinese (1.5G of RAM). you
might try http://www.yale.edu/chinesemac to see if they have
any more details.
\_ thx. saw this site before, but didn't have a clue to which
plugin might be good. I think we may get her mac this
weekend. :-)
\_ I use a Tablet PC to write Chinese. Nothing is more
nature than writing Chinese and having it converted
with over 99% recognition rate. It's amazing.
\_ way cool! |
| 12/23 |