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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...
How do I prevent site scraping? [closed]
...es, these work by extracting data from pages based on patterns in HTML, usually ignoring everything else.
For example: If your website has a search feature, such a scraper might submit a request for a search, and then get all the result links and their titles from the results page HTML, in order t...
What is the role of the bias in neural networks? [closed]
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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...
The JPA hashCode() / equals() dilemma
...als() implementation should be used for JPA entity classes. Most (if not all) of them depend on Hibernate, but I'd like to discuss them JPA-implementation-neutrally (I am using EclipseLink, by the way).
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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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When should I use the “strictfp” keyword in java?
I've looked up what this does, but does anyone actually have an example of when you would use the strictfp keyword in Java? Has anyone actually found a use for this?
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Android: Background Image Size (in Pixel) which Support All Devices
I am creating an Application which will run on all Android Devices. I want to create xhdpi Graphics for My App. My App is full screen. I am confused in Creating graphics. can any one tell me the best sizes of my background image in pixels.
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How to validate phone numbers using regex
...trying to put together a comprehensive regex to validate phone numbers. Ideally it would handle international formats, but it must handle US formats, including the following:
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What is the difference between Bower and npm?
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All package managers have many downsides. You just have to pick which you can live with.
History
npm started out managing node.js modules (that's why packages go into node_modules by default), but it works for the front-end...
Move all files except one
How can I move all files except one? I am looking for something like:
14 Answers
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