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@qwo
qwo / google-tips
Last active May 8, 2025 09:25
Google Recruiter Candidate Tips ..
xxx,
Thanks again for taking the time to speak with me and for sending me your information. I'm excited to tell you that we would like to move forward in the process!
One of our coordinators will be emailing you within the next week from an @google.com domain with the date and time of your phone interview. In the meantime, I've included some preparation materials (below.)
Please note this will be a technical interview that will last for approximately 45 minutes. Google takes an academic approach to the interviewing process. This means that we are interested in your thought process, your approach to problem solving as well as your coding abilities. You may be asked questions that relate to technical knowledge, algorithms, coding, performance, how to test solutions, and perhaps your interest in Google products. The best advice that I can give you is to treat the interview like a conversation, talk through the problems, and please feel free to ask the interviewer if you are not clear with any of the questio
@tototoshi
tototoshi / rownum.sql
Created December 26, 2012 01:14
Grouped LIMIT in PostgreSQL: show the first N rows for each group
-- http://stackoverflow.com/questions/1124603/grouped-limit-in-postgresql-show-the-first-n-rows-for-each-group
-- http://www.postgresql.jp/document/9.2/html/tutorial-window.html
CREATE TABLE empsalary (
depname varchar(10) not null
, empno integer not null
, salary integer not null
);
INSERT INTO empsalary (depname, empno, salary) VALUES ('develop', 11, 5200);
@jboner
jboner / latency.txt
Last active July 28, 2026 14:30
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference 0.5 ns
Branch mispredict 5 ns
L2 cache reference 7 ns 14x L1 cache
Mutex lock/unlock 25 ns
Main memory reference 100 ns 20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy 3,000 ns 3 us
Send 1K bytes over 1 Gbps network 10,000 ns 10 us
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD