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How to find the JVM version from a program?
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That JMX call returns the equivalent of "java.vm.version", not "java.version". These are usually (but not necessarily) the same.
– Alex Miller
Jun 21 '13 at 15:54
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Is there a REAL performance difference between INT and VARCHAR primary keys?
... and a coworker won't budge on the INT AUTO_INCREMENT as a primary key for all tables.
14 Answers
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Why do I need an IoC container as opposed to straightforward DI code? [closed]
...ain can become nested, and it quickly becomes unwieldy to wire them up manually. Even with factories, the duplication of your code is just not worth it.
IoC containers can be complex, yes. But for this simple case I've shown it's incredibly easy.
Okay, let's justify this even more. Let's say ...
Fastest way to get the first object from a queryset in django?
...eturn None if there aren't any. There are lots of ways to do this which all work. But I'm wondering which is the most performant.
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How to wait for several Futures?
...ave several futures and need to wait until either any of them fails or all of them succeed.
8 Answers
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How do you run your own code alongside Tkinter's event loop?
...tion for the after method:
def after(self, ms, func=None, *args):
"""Call function once after given time.
MS specifies the time in milliseconds. FUNC gives the
function which shall be called. Additional parameters
are given as parameters to the function call. Return
identifier...
Average of 3 long integers
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This code will work, but isn't that pretty.
It first divides all three values (it floors the values, so you 'lose' the remainder), and then divides the remainder:
long n = x / 3
+ y / 3
+ z / 3
+ ( x % 3
+ y % 3
+ z % 3
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Try catch statements in C
... exceptions but you can simulate them to a degree with setjmp and longjmp calls.
static jmp_buf s_jumpBuffer;
void Example() {
if (setjmp(s_jumpBuffer)) {
// The longjmp was executed and returned control here
printf("Exception happened here\n");
} else {
// Normal code execution s...
Android: upgrading DB version and adding new table
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1. About onCreate() and onUpgrade()
onCreate(..) is called whenever the app is freshly installed. onUpgrade is called whenever the app is upgraded and launched and the database version is not the same.
2. Incrementing the db version
You need a constructor like:
MyOpenHelp...
How do you get a query string on Flask?
...ut since this answer correctly answers the question my Google search terms alluded to ('flask get request parameter') I'm up-voting it anyhow. I'm a pedant too, but I'm chalking this up to web mysticism. ????
– Michael Scheper
Jan 13 '17 at 23:45
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