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What's the difference between JPA and Spring Data JPA?
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edited Jun 20 at 9:12
Community♦
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answered Apr 22 '13 at 13:36
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How to create a MySQL hierarchical recursive query
...e in statements other than SET. This functionality is supported in MySQL 8.0 for backward compatibility but is subject to removal in a future release of MySQL.
As stated above, from MySQL 8.0 onward you should use the recursive with syntax.
Efficiency
For very large data sets this solution might...
What is a NullReferenceException, and how do I fix it?
... p1.Books.Add(...) statements.
Array
int[] numbers = null;
int n = numbers[0]; // numbers is null. There is no array to index.
Array Elements
Person[] people = new Person[5];
people[0].Age = 20 // people[0] is null. The array was allocated but not
// initialized. There is no Pers...
Does Parallel.ForEach limit the number of active threads?
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No, it won't start 1000 threads - yes, it will limit how many threads are used. Parallel Extensions uses an appropriate number of cores, based on how many you physically have and how many are already busy. It allocates work for each core and the...
What's the difference between Invoke() and BeginInvoke()
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answered Oct 23 '08 at 12:40
Jon SkeetJon Skeet
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How to understand nil vs. empty vs. blank in Ruby
...used on strings, arrays and hashes and returns true if:
String length == 0
Array length == 0
Hash length == 0
Running .empty? on something that is nil will throw a NoMethodError.
That is where .blank? comes in. It is implemented by Rails and will operate on any object as well as work like .empt...
What does “static” mean in C?
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1550
A static variable inside a function keeps its value between invocations.
A static global variab...
When to use an object instance variable versus passing an argument to the method
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answered Dec 6 '08 at 10:45
TomTom
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How do I initialize an empty array in C#?
...te an empty array you can do this:
string[] emptyStringArray = new string[0];
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Determine if a String is an Integer in Java [duplicate]
... get.
public static boolean isInteger(String s) {
return isInteger(s,10);
}
public static boolean isInteger(String s, int radix) {
if(s.isEmpty()) return false;
for(int i = 0; i < s.length(); i++) {
if(i == 0 && s.charAt(i) == '-') {
if(s.length() == 1) r...