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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.
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Does MySQL index foreign key columns automatically?
Does MySQL index foreign key columns automatically?
9 Answers
9
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JSON Array iteration in Android/Java
...or iterator() {
return this.myArrayList.iterator();
}
This will make all instances of JSONArray iterable, meaning that the for (Object foo : bar) syntax will now work with it (note that foo has to be an Object, because JSONArrays do not have a declared type). All this works because the JSONArr...
.NET - Dictionary locking vs. ConcurrentDictionary
... a can from a pyramid-can while a clerk is currently building the pyramid, all hell would break loose. Or, what if two customers reaches for the same item at the same time, who wins? Will there be a fight? This is a non-threadsafe-collection. There's plenty of ways to avoid problems, but they all re...
What is the difference between an int and an Integer in Java and C#?
...by reference (or more accurately have references passed by value), and are allocated from the heap. Conversely, primitives are immutable types that are passed by value and are often allocated from the stack.
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How do I remove the file suffix and path portion from a path string in Bash?
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This is probably the most flexible of all the answers posted, but I think the answers suggesting the basename and dirname commands deserve some attention as well. They may be just the trick if you don't need any other fancy pattern matching.
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Horizontal ListView in Android?
Is it possible to make the ListView horizontally? I have done this using a gallery view, but the selected item comes to the center of the screen automatically. I don't want the selected item at the same spot I clicked. How can I rectify this problem? My idea was to set the ListView with a horizo...
Parcelable encountered IOException writing serializable object getactivity()
...the stack trace and work your way up to the last Caused by line. That's usually going to point to the specific problem. All the other stanzas of the stack trace represent wrapped exceptions around the "real" exception at the bottom of the trace.
– CommonsWare
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Ways to save enums in database
...nd it is much more worth it to help when you're having a problem.
Additionally, if you use numerical values, you are tied to them. You cannot nicely insert or rearrange the members without having to force the old numerical values. For example, changing the Suit enumeration to:
public enum Suit { U...
Delete first character of a string in Javascript
..."foobar";
var s2 = s1.substring(1);
alert(s2); // shows "oobar"
To remove all 0's at the start of the string:
var s = "0000test";
while(s.charAt(0) === '0')
{
s = s.substring(1);
}
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