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.NET - Dictionary locking vs. ConcurrentDictionary
...gging the clerk, this will anger the other customers in line behind you.
Now consider this. In the store with one clerk, what if you get all the way to the front of the line, and ask the clerk "Do you have any toilet paper", and he says "Yes", and then you go "Ok, I'll get back to you when I know ...
Delete multiple records using REST
...so it doesn't matter how you specify your API, they are not privy to this knowledge so cannot behave differently.
– Nicholas Shanks
Feb 18 '14 at 20:00
3
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must appear in the GROUP BY clause or be used in an aggregate function
...erver just don't allow this at all. Mysql used to allow it by default, but now since 5.7 the administrator needs to enable this option (ONLY_FULL_GROUP_BY) manually in the server configuration for this feature to be supported...
...
Options, Settings, Properties, Configuration, Preferences — when and why?
...s style was ‘Options’ on the ‘Tools’ menu, though all bets are off now as more MS apps drop the menu bar and throw the old predictable controls all over the place with no consistent pettern.
RISC OS style was ‘Choices’ on the icon bar menu, just to add yet another pointless possibility....
How Do I Choose Between a Hash Table and a Trie (Prefix Tree)?
...suffixes as well, by hash-consing.
Advantages of hashtables:
Everyone knows hashtables, right? Your system will already have a nice well-optimized implementation, faster than tries for most purposes.
Your keys need not have any special structure.
More space-efficient than the obvious linked tri...
pyplot scatter plot marker size
...20*2**n for n in range(len(x))]
plt.scatter(x,y,s=s)
plt.show()
gives
Now the apparent size of the markers increases roughly linearly in an intuitive fashion.
As for the exact meaning of what a 'point' is, it is fairly arbitrary for plotting purposes, you can just scale all of your sizes by a ...
What's the best way to check if a file exists in C?
... == EEXIST) {
/* the file already existed */
...
}
} else {
/* now you can use the file */
}
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Is there a “previous sibling” selector?
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@ArchLinuxTux: "This limitation is now removed", so once upon of time we possibly can use this feature :D.
– Jacob van Lingen
Feb 12 at 11:57
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What is the fastest way to get the value of π?
...ll depends on what kind of accuracy you are looking for. The fastest π I know of is the one with the digits hard coded. Looking at Pi and Pi[PDF], there are a lot of formulae.
Here is a method that converges quickly — about 14 digits per iteration. PiFast, the current fastest application, uses t...
What are the best practices for using a GUID as a primary key, specifically regarding performance?
...ve page and index fragmentation and to generally bad performance.
Yes, I know - there's newsequentialid() in SQL Server 2005 and up - but even that is not truly and fully sequential and thus also suffers from the same problems as the GUID - just a bit less prominently so.
Then there's another issu...