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MySQL “Group By” and “Order By”
...olumns in a SELECT with a GROUP BY clause is non-standard. MySQL will generally return the values of the first row it finds and discard the rest. Any ORDER BY clauses will only apply to the returned column value, not to the discarded ones.
IMPORTANT UPDATE
Selecting non-aggregate columns used to wor...
Can I set background image and opacity in the same property?
... Yeah, the big problem with a PNG is the size. It is likely going to be really large. Now that we can specify opacity: ... in all browsers, it way better!
– Alexis Wilke
Jul 1 '17 at 23:49
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How to directly initialize a HashMap (in a literal way)?
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All Versions
In case you happen to need just a single entry: There is Collections.singletonMap("key", "value").
For Java Version 9 or higher:
Yes, this is possible now. In Java 9 a couple of factory methods have been added...
Do spurious wakeups in Java actually happen?
...hread_cond_wait() function in Linux is implemented using the futex system call. Each blocking system call on Linux returns abruptly with EINTR when the process receives a signal. ... pthread_cond_wait() can't restart the waiting because it may miss a real wakeup in the little time it was outside the...
What exactly does git rebase --skip do?
...lready existed upstream, Git will not be able to apply your commit (but usually should skip it automatically, if the patch is exactly the same). Your own commit will be skipped, but the change will still exist in current HEAD, because it was already applied upstream.
You should really make sure you...
REST API Token-based Authentication
...e over HTTP, I reasoned that we would dispense tokens to avoid repeatedly calling the authentication service. Which brings me neatly to my first question:
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Java: Path vs File
...e modern java.nio.file lib, and does everything java.io.File can, but generally in a better way, and more.
For new projects, use Path.
And if you ever need a File object for legacy, just call Path#toFile()
Migrating from File to Path
This Oracle page highlights differences, and maps java.io.Fil...
Gmail Error :The SMTP server requires a secure connection or the client was not authenticated. The s
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This generally happens when you try login from different time zone or IP Address Computer. Your production server and the mail id you have used both are in different time zone. Choose either of these two solutions:
1) Log in to produc...
svn: replace trunk with branch
... try it? IIRC, SVN shows that the files were deleted and readded but internally, it will know that the files have been moved.
– Aaron Digulla
Sep 27 '10 at 7:12
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Exact time measurement for performance testing [duplicate]
... is the most exact way of seeing how long something, for example a method call, took in code?
7 Answers
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