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How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
... preferred whenever practical.
In this case, you typically follow the following process:
CREATE a TEMPORARY table
COPY or bulk-insert the new data into the temp table
LOCK the target table IN EXCLUSIVE MODE. This permits other transactions to SELECT, but not make any changes to the table.
Do an ...
vs
...gured to serve files in ISO-8859-1 by default, so you need to add the following line to your .htaccess file:
AddDefaultCharset UTF-8
This will configure Apache to serve your files declaring UTF-8 encoding in the Content-Type response header, but your files must be saved in UTF-8 (without BOM) to ...
How does BLAS get such extreme performance?
...t all).
IMHO no BLAS implementation uses algorithms like the Coppersmith–Winograd algorithm or the Strassen algorithm. The likely reasons are:
Maybe its not possible to provide a cache optimized implementation of these algorithms (i.e. you would loose more then you would win)
These algorithms a...
Why not use java.util.logging?
...ultimately you decide not to care about popular opinion, consider the following facts:
those who prefer j.u.l do so out of convenience because j.u.l is bundled with the JDK. To my knowledge there are no other objective arguments in favor of j.u.l.
your own preference for j.u.l is just that, a pref...
Can dplyr package be used for conditional mutating?
...adability for myself and others, but in this case it seems like data.table wins.
– Paul McMurdie
Feb 7 at 19:50
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Escape double quotes in parameter
... Ha! I never would have guessed it was wscript's fault! Leave it to Windows :)
– Bryan Field
Oct 13 '11 at 21:41
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Check if at least two out of three booleans are true
...;
Thread.sleep(1000);
}
}
}
This prints the following on my machine (running Ubuntu on Intel Core 2 + sun java 1.6.0_15-b03 with HotSpot Server VM (14.1-b02, mixed mode)):
First and second iterations:
a&&b || b&&c || a&&c : 1740 ms
a ? b||c : b&...
How can you program if you're blind?
...everal programming internships so my answer will be based off these. I use windows xp as my operating system and Jaws to read what appears on the screen to me in synthetic speech. For java programming I use eclipse, since it’s a fully featured IDE that is accessible.
In my experience as a genera...
Protecting executable from reverse engineering?
...te the modified code much more often than you modify it, it may still be a win).
– jilles
Jun 26 '11 at 12:55
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How does the Amazon Recommendation feature work?
...nearest neighbor methods, and neural networks. Here are some papers by the winning team:
R. Bell, Y. Koren, C. Volinsky, "The BellKor 2008 Solution to the Netflix Prize", (2008).
A. Töscher, M. Jahrer, “The BigChaos Solution to the Netflix Prize 2008", (2008).
A. Töscher, M. Jahrer, R. Legens...