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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...
Padding is invalid and cannot be removed?
...t are the same. The padding method even if not explicitly set should still allow for proper decryption/encryption (if not set they will be the same). However if you for some reason are using a different set of keys for decryption than used for encryption you will get this error:
Padding is inval...
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)?
...
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...
git rebase, keeping track of 'local' and 'remote'
...m points out that, in a GUI mergetool context:
local references the partially rebased commits: "ours" (the upstream branch)
remote refers to the incoming changes: "theirs" - the current branch before the rebase.
See illustrations in the last part of this answer.
Inversion when rebase
The co...
No output to console from a WPF application?
...
You'll have to create a Console window manually before you actually call any Console.Write methods. That will init the Console to work properly without changing the project type (which for WPF application won't work).
Here's a complete source code example, of how a C...
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...
Are strongly-typed functions as parameters possible in TypeScript?
...f the types of its argument and its return type. Here we specify that the callback parameter's type must be "function that accepts a number and returns type any":
class Foo {
save(callback: (n: number) => any) : void {
callback(42);
}
}
var foo = new Foo();
var strCallback = (re...
How to set JVM parameters for Junit Unit Tests?
...t app that will only run with sufficient heap-space, and will be run internally on Win 7 64-bit machines - so redesigning the tests isn't a practical suggestion.)
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Parameterize an SQL IN clause
...er 7 and later will auto-parameterize queries, so using parameters isn't really necessary from a performance standpoint - it is, however, critical from a security standpoint - especially with user inputted data like this.
sh...