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Difference between save and saveAndFlush in Spring data jpa
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sorry but if I save an entity and again the same one, you mean with save the second command won't throw an exception for duplication for example??
– azerafati
Jul 5 '14 at 12:23
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What are copy elision and return value optimization?
...py was made.
Hello World!
A copy was made.
Hello World!
This also means fewer objects can be created, so you also can't rely on a specific number of destructors being called. You shouldn't have critical logic inside copy/move-constructors or destructors, as you can't rely on them being call...
How to write multiple line property value using PropertiesConfiguration?
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If you mean the following; that just relies on backslash + end-of-line. I just found it documented in:
http://docs.oracle.com/javase/6/docs/api/java/util/Properties.html
primes = 2,\
3,\
5,\
7,\
11
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must appear in the GROUP BY clause or be used in an aggregate function
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@amenzhinsky What do you mean? If one wants to have the result set sorted with a different order than BY cname ?
– ypercubeᵀᴹ
Nov 26 '14 at 13:19
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Principal component analysis in Python
... PCA does not center or scale A; you usually want to first
A -= A.mean(A, axis=0)
A /= A.std(A, axis=0)
with the little class Center or the like, below.
See also:
http://en.wikipedia.org/wiki/Principal_component_analysis
http://en.wikipedia.org/wiki/Singular_value_decom...
Regex how to match an optional character
.... {1} is redundant. (Of course you could also write [A-Z]{0,1} which would mean the same, but that's what the ? is there for.)
You could improve your regex to
^([0-9]{5})+\s+([A-Z]?)\s+([A-Z])([0-9]{3})([0-9]{3})([A-Z]{3})([A-Z]{3})\s+([A-Z])[0-9]{3}([0-9]{4})([0-9]{2})([0-9]{2})
And, since in m...
How to ignore xargs commands if stdin input is empty?
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You mean brew install findutils. findutils, not fileutils.
– Mitar
Dec 4 '16 at 20:38
4
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How to create and write to a txt file using VBA
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@RickHenderson, I prefer it, if that's what you mean. The advantage is encapsulation. Once you object (set oFile = Nothing|), or it goes out of scope, the file is automatically closed.
– Ben
Jun 8 '16 at 8:59
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mysqli or PDO - what are the pros and cons? [closed]
... it is just a procedural API that has been objectified, if you know what I mean. In short, I find PDO easier to work with, but that is of course subjective.
share
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Invert “if” statement to reduce nesting
...or expression can cause a control flow that causes the method to end. This means clean-up must be done through using the finally or using keywords.
Anyway, I'm saying I think a lot of people quote the 'only return at the end of a method' guideline without understanding why it was ever a good thing ...