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MySQL Error 1215: Cannot add foreign key constraint
I am trying to forward engineer my new schema onto my db server, but I can't figure out why I am getting this error. I've tried to search for the answer here, but everything I've found has said to either set the db engine to Innodb or to make sure the keys I'm trying to use as a foreign key are pri...
The remote end hung up unexpectedly while git cloning
My git client repeatedly fails with the following error after trying to clone the repository for some time.
36 Answers
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ListView item background via custom selector
...
I've been frustrated by this myself and finally solved it. As Romain Guy hinted to, there's another state, "android:state_selected", that you must use. Use a state drawable for the background of your list item, and use a different state drawable for list...
Sum a list of numbers in Python
... divisor instead of 2.
Thus:
averages = [(x + y) / 2.0 for (x, y) in zip(my_list[:-1], my_list[1:])]
Question 2:
That use of sum should work fine. The following works:
a = range(10)
# [0,1,2,3,4,5,6,7,8,9]
b = sum(a)
print b
# Prints 45
Also, you don't need to assign everything to a variable...
What to use as an initial version? [closed]
I usually start my projects with a version 1.0.0. As soon as I have some stuff together, I release it as 1.0.0 and move on with 1.1.0.
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Merge two (or more) lists into one, in C# .NET
...re not creating the list with the correct final size - whereas the code in my answer does. Do that, and the 10000*10000 test is faster using AddRange, at least - although other results are inconsistent. (You should also force garbage collection between tests - and I'd argue that the very short tests...
Rails - How to use a Helper Inside a Controller
...realize you are supposed to use a helper inside a view, I need a helper in my controller as I'm building a JSON object to return.
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Why do std::shared_ptr work
...{
delete static_cast<T*>(p);
}
template <typename T>
class my_unique_ptr {
std::function< void (void*) > deleter;
T * p;
template <typename U>
my_unique_ptr( U * p, std::function< void(void*) > deleter = &delete_deleter<U> )
: p(p), deleter(d...
Find Java classes implementing an interface [duplicate]
...rary. You can use reflection, but ASM turned out to perform better.
I put my package in an open source library I have on my web site. The library is here: http://software.clapper.org/javautil/. You want to start with the with ClassFinder class.
The utility I wrote it for is an RSS reader that I st...
A connection was successfully established with the server, but then an error occurred during the pre
...d Project.
3) Reset IIS
4) Run the project again.
Basically that solved my problem, but in my case i was not getting this error and suddenly my local environment starts giving me above error, so may be that trick work for me.
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