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What are the pros and cons of performing calculations in sql vs. in your application
...lations like SUM(), AVG(),MIN(), MAX() here the database engine will be an order of magnitude faster than a Java implementation.
Anywhere the calculation is used to filter rows. Filtering at the DB is much more efficient than reading a row and then discarding it.
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How do the likely/unlikely macros in the Linux kernel work and what is their benefit?
...dd $0x8,%rsp
34: c3 retq
The instruction order in memory was unchanged: first the printf and then puts and the retq return.
With __builtin_expect
Now replace if (i) with:
if (__builtin_expect(i, 0))
and we get:
0000000000000000 <main>:
0: 48 83 ...
What is the default location for MSBuild logs?
...sproj /t:Clean
You can also specify multiple MSBuild.EXE command lines in order to build multiple projects. For the usual build-the-entire-solution outcome you can target only the final end assemblies and let the dependency graph generate the individual targets.
This will produce a .log file, w...
How do I get the path of the Python script I am running in? [duplicate]
...olution would work only if it is called at the beginning of the script (in order to be sure that nobody changes the current directory). I am inclined to use the inspect method instead. "running script" is not necessarily same as "called script" (entry point) or "currently running script".
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Get the position of a div/span tag
...ately this method fails in Chrome when the element is inside a table with border. It will also fail in IE6 standards mode due to BODY margins.
– GetFree
Jul 17 '12 at 21:17
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Git: what is a dangling commit/blob and where do they come from?
...commit to parent commit. We need a reference to the latest child commit in order to reach the older commits on a branch.
PS - The above diagram and understanding was obtained from this free course. Even though the course is quite old, the knowledge is still relevant.
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Getting individual colors from a color map in matplotlib
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In order to get rgba integer value instead of float value, we can do
rgba = cmap(0.5,bytes=True)
So to simplify the code based on answer from Ffisegydd, the code would be like this:
#import colormap
from matplotlib import cm...
Why does cURL return error “(23) Failed writing body”?
...simple Unix program that reads the entire input page and reverses the line order (hence we run it twice). Because it has to read the whole input to find the last line, it will not output anything to grep until cURL is finished. Grep will still close the read stream when it has what it's looking for,...
Copy a stream to avoid “stream has already been operated upon or closed”
...here the developer is forced to store intermediate results (collecting) in order to process a stream in two different ways. The implication that the stream is generated more than once (unless you collect it) seems clear - because otherwise you wouldn't need a collect method.
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Are parallel calls to send/recv on the same socket valid?
...ifferent threads, the OS will handle the synchronization.
However, if the order of sending/receiving is semantically significant, you yourself (respectively your code) have to ensure proper sequencing between the operations in the different threads - as is always the case with threads.
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