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Best way to test if a row exists in a MySQL table
... Thanks for the additional answer. Did you find the difference in time between the two fastest options for a TEXT field to be pretty consistent? The difference doesn't seem large, and using SELECT EXISTS(SELECT 1 ... LIMIT 1) seems to be pretty good in both cases.
– Be...
How to print like printf in Python3?
... Not the least of which is you can reference the same format only multiple times or out of order: "{1}, {1}, {0}, and {1} ".format("eggs","spam")=="spam, spam, eggs, and spam"
– Dr Xorile
Feb 12 '18 at 14:45
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Parse string to DateTime in C#
I have date and time in a string formatted like that one:
8 Answers
8
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Python, compute list difference
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@NeilG Do you consider time consumed to build the set? In my case (both lists have about 10M strings) time to build two sets and subtract them is considerably larger than building one set and iterating over the list.
– dimril
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Measuring elapsed time with the Time module
With the Time module in python is it possible to measure elapsed time? If so, how do I do that?
10 Answers
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Method call if not null in C#
...enchmark I did indicates that handling an event with no subscribers is 2-3 times slower when using the the "default delegate" pattern. (On my dual core 2.5GHz laptop that means 279ms : 785ms for raising 50 million not-subscribed events.). For application hot spots, that might be an issue to consider...
Functions that return a function
...ion is still callable. It still exists. This is used in JavaScript all the time. Functions can be passed around just like other values. Consider the following:
function counter() {
var count = 0;
return function() {
alert(count++);
}
}
var count = counter();
count();
count();
co...
Can C++ code be valid in both C++03 and C++11 but do different things?
...1) >>(2);
// fon<fun<4> >(2) in C++03
// Compile time error in C++11
unsigned int B = fon< fun< 9 >>(1) > >(2);
}
Operator new may now throw other exceptions than std::bad_alloc
struct foo { void *operator new(size_t x){ throw std::exception(); } }
tr...
How to display line numbers in 'less' (GNU)
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wow, I have looked at the help for less dozens of times hoping to find the answer to this. I have always overlooked "-<flag> Toggle a command line option [see OPTIONS below]." ...which means you can type "-N" from within less. I have been annoyed by this for about a de...
What is the best way to measure execution time of a function? [duplicate]
Obviously I can do and DateTime.Now.After - DateTime.Now.Before but there must be something more sophisticated.
4 Answ...