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Can javax.persistence.Query.getResultList() return null?
...pecification says nothing about it. But Java Persistence with Hibernate book, 2nd edition, says:
If the query result is empty, a null is returned
Hibernate JPA implementation (Entity Manager) return null when you call query.getResultList() with no result.
UPDATE
As pointed out by some users,...
method overloading vs optional parameter in C# 4.0 [duplicate]
... parameters.
For example say you want a method foo to be be called/used like so, foo(), foo(1), foo(1,2), foo(1,2, "hello"). With method overloading you would implement the solution like this,
///Base foo method
public void DoFoo(int a, long b, string c)
{
//Do something
}
/// Foo with 2 par...
Tricks to manage the available memory in an R session
What tricks do people use to manage the available memory of an interactive R session? I use the functions below [based on postings by Petr Pikal and David Hinds to the r-help list in 2004] to list (and/or sort) the largest objects and to occassionally rm() some of them. But by far the most effect...
How do I find and view a TFS changeset by comment text?
... but I don't see a simple way in the Source Control Explorer to do this task?
11 Answers
...
1052: Column 'id' in field list is ambiguous
...mended approach -- why type more than you have to?
Why Do These Queries Look Different?
Secondly, my answers use ANSI-92 JOIN syntax (yours is ANSI-89). While they perform the same, ANSI-89 syntax does not support OUTER joins (RIGHT, LEFT, FULL). ANSI-89 syntax should be considered deprecated, the...
iOS Detect 3G or WiFi
...y reachabilityForInternetConnection];
[reachability startNotifier];
NetworkStatus status = [reachability currentReachabilityStatus];
if(status == NotReachable)
{
//No internet
}
else if (status == ReachableViaWiFi)
{
//WiFi
}
else if (status == ReachableViaWWAN)
{
//3G
}
...
How to get the ASCII value of a character
...ould get the int value
of the char. And in case you want to
convert back after playing with the
number, function chr() does the trick.
>>> ord('a')
97
>>> chr(97)
'a'
>>> chr(ord('a') + 3)
'd'
>>>
In Python 2, there is also the unichr function, returning...
Python: How do I make a subclass from a superclass?
In Python, how do you make a subclass from a superclass?
11 Answers
11
...
Set angular scope variable in markup
...
ng-init does not work when you are assigning variables inside loop. Use
{{myVariable=whatever;""}}
The trailing "" stops the Angular expression being evaluated to any text.
Then you can simply call {{myVariable}} to output your variable value....
How to continue a Docker container which has exited
...n existing container after it exited and your changes are still there.
docker start `docker ps -q -l` # restart it in the background
docker attach `docker ps -q -l` # reattach the terminal & stdin
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