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JPA OneToMany not deleting child
...em with a simple @OneToMany mapping between a parent and a child entity. All works well, only that child records are not deleted when I remove them from the collection.
...
JavaScript: Class.method vs. Class.prototype.method
... are extending the constructor function prototype, it will be available to all the object instances created with the new keyword, and the context within that function (the this keyword) will refer to the actual object instance where you call it.
Consider this example:
// constructor function
funct...
How should a model be structured in MVC? [closed]
...understand MVC-like patterns in the context of PHP-based web applications. All the external links that are used in the content are there to explain terms and concepts, and not to imply my own credibility on the subject.
The first thing that I must clear up is: the model is a layer.
Second: there ...
How Does Modulus Divison Work
I don't really understand how modulus division works.
I was calculating 27 % 16 and wound up with 11 and I don't understand why.
...
demystify Flask app.secret_key
If app.secret_key isn't set, Flask will not allow you to set or access the session dictionary.
2 Answers
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What is eager loading?
...hing when asked. Classic example is when you multiply two matrices. You do all the calculations. That's eager loading;
Lazy loading: you only do a calculation when required. In the previous example, you don't do any calculations until you access an element of the result matrix; and
Over-eager loadin...
How can I grep for a string that begins with a dash/hyphen?
...rep still has it's own meaning to dashes (by providing options).
So you really need to escape it twice (if you prefer not to use the other mentioned answers). The following will/should work
grep \\-X
grep '\-X'
grep "\-X"
One way to try out how Bash passes arguments to a script/program is to cre...
Why can't the C# constructor infer type?
...type inference?
No. When you have
new Foo(bar)
then we could identify all types called Foo in scope regardless of generic arity, and then do overload resolution on each using a modified method type inference algorithm. We'd then have to create a 'betterness' algorithm that determines which of t...
Loading a properties file from Java package
...).getResourceAsStream("foo.properties");
prop.load(in);
in.close();
(Add all the necessary exception handling).
If your class is not in that package, you need to aquire the InputStream slightly differently:
InputStream in =
getClass().getResourceAsStream("/com/al/common/email/templates/foo.pro...
Why is quicksort better than mergesort?
...use many factors influence an algorithm’s runtime, and, when taking them all together, quicksort wins out.
In particular, the often-quoted runtime of sorting algorithms refers to the number of comparisons or the number of swaps necessary to perform to sort the data. This is indeed a good measure ...