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How to select rows with no matching entry in another table?
... t2.ID IS NULL
The key points are:
LEFT JOIN is used; this will return ALL rows from Table1, regardless of whether or not there is a matching row in Table2.
The WHERE t2.ID IS NULL clause; this will restrict the results returned to only those rows where the ID returned from Table2 is null - in o...
What is the role of the bias in neural networks? [closed]
...
I think that biases are almost always helpful. In effect, a bias value allows you to shift the activation function to the left or right, which may be critical for successful learning.
It might help to look at a simple example. Consider this 1-input, 1-output network that has no bias:
The ou...
How to delete shared preferences data from App in Android
...: SharedPreferences.Editor.remove() followed by a commit()
To remove them all SharedPreferences.Editor.clear() followed by a commit()
If you don't care about the return value and you're using this from your application's main thread, consider using apply() instead.
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How do I paste multi-line bash codes into terminal and run it all at once?
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I'm really surprised this answer isn't offered here, I was in search of a solution to this question and I think this is the easiest approach, and more flexible/forgiving...
If you'd like to paste multiple lines from a website/text...
What does “Changes not staged for commit” mean
...epository, you have to git add it again if you want it to be staged.
This allows you to commit only a subset of the changes you made since the last commit. For example, let's say you have file a, file b and file c. You modify file a and file b but the changes are very different in nature and you do...
Internal typedefs in C++ - good style or bad style?
...) or whatever. Esp. if it's a shared pointer, I don't provide a typedef at all, but keep the shared_ptr use explicitly in the code.
Actually, I hardly ever use typedefs outside Template Metaprogramming.
The STL does this type of thing all the time
The STL design with concepts defined in terms...
The Definitive C++ Book Guide and List
...tour” is a quick (about 180 pages and 14 chapters) tutorial overview of all of standard C++ (language and standard library, and using C++11) at a moderately high level for people who already know C++ or at least are experienced programmers. This book is an extended version of the material that con...
Waiting on a list of Future
...//4 tasks
for(int i = 0; i < 4; i++) {
completionService.submit(new Callable<SomeResult>() {
public SomeResult call() {
...
return result;
}
});
}
int received = 0;
boolean errors = false;
while(received < 4 && !errors) {
Future&l...
Can I change all my http:// links to just //?
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I tested it thoroughly before publishing. Of all the browsers available to test against on Browsershots, I could only find one that did not handle the protocol relative URL correctly: an obscure *nix browser called Dillo.
There are two drawbacks I've received feedback ...
Xcode “The private key for is not installed on this mac - distributing”
...list of signing identities.
Go back to the developer website and make sure all your provisioning profiles are configured with the new certificate. (They should all be listed as Active when you are done.)
Go back to XCode and refresh your list of provisioning profiles.
I had the same issue as you d...