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What is the difference between persist() and merge() in JPA and Hibernate?
...these
other entities are annotated with the
cascade=PERSIST or cascade=ALL
annotation element value or specified
with the equivalent XML descriptor
element.
If X is a removed entity,
it becomes managed.
If X is a
detached object, the
EntityExistsException may be thrown
when the...
@property retain, assign, copy, nonatomic in Objective-C
...gners opted for the safer of the two solutions. In fact nonatomic is generally the better choice as it omits extremely expensive thread locks. The only reason to use atomic is if your property might be set from multiple threads (in which case omitting it can lead to an over-release or a leak).
...
HTML/CSS: Making two floating divs the same height
... peculiar problem that I currently solve using a table , see below. Basically, I want to have two divs take up 100% of the available width, but only take up as much vertical space as needed (which isn't really that obvious from the picture). The two should at all times have the exact same height ...
What is the difference between an interface and abstract class?
...'t do anything. It's just a pattern.
For example (pseudo code):
// I say all motor vehicles should look like this:
interface MotorVehicle
{
void run();
int getFuel();
}
// My team mate complies and writes vehicle looking that way
class Car implements MotorVehicle
{
int fuel;
vo...
How do I remove objects from a JavaScript associative array?
...rray, if you do not want to create a sparsely populated array - and you usually don't - then you should use Array#splice or Array#pop.
Note that the delete operator in JavaScript does not directly free memory. Its purpose is to remove properties from objects. Of course, if a property being deleted ...
Find the version of an installed npm package
How to find the version of an installed node.js/npm package ?
27 Answers
27
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How to make code wait while calling asynchronous calls like Ajax [duplicate]
...
Use callbacks. Something like this should work based on your sample code.
function someFunc() {
callAjaxfunc(function() {
console.log('Pass2');
});
}
function callAjaxfunc(callback) {
//All ajax calls called here
o...
Convert data.frame column format from character to factor
...e to the world of R.
mtcars #look at this built in data set
str(mtcars) #allows you to see the classes of the variables (all numeric)
#one approach it to index with the $ sign and the as.factor function
mtcars$am <- as.factor(mtcars$am)
#another approach
mtcars[, 'cyl'] <- as.factor(mtcars[...
Is there a way to auto expand objects in Chrome Dev Tools?
... SINGLE TIME :) Is there a shortcut or setting to have this done automatically?
13 Answers
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Where to place the 'assets' folder in Android Studio?
...assets folder. It doesn't come auto-created in Android Studio, and almost all the forums in which this is discussed talk about Eclipse.
...