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What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
The "N+1 selects problem" is generally stated as a problem in Object-Relational mapping (ORM) discussions, and I understand that it has something to do with having to make a lot of database queries for something that seems simple in the object world.
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Working with select using AngularJS's ng-options
...o work... note the ng-model="blah" which is saying "set $scope.blah to the selected value".
Try this:
<select ng-model="blah" ng-options="item.ID as item.Title for item in items"></select>
Here's more from AngularJS's documentation (if you haven't seen it):
for array data sources...
Get selected option from select element
I am trying to get the selected option from a dropdown and populate another item with that text, as follows. IE is barking up a storm and it doesn't work in Firefox:
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Difference between decimal, float and double in .NET?
...a double/float.
Decimals and Floats/Doubles cannot be compared without a cast whereas Floats and Doubles can. Decimals also allow the encoding or trailing zeros.
float flt = 1F/3;
double dbl = 1D/3;
decimal dcm = 1M/3;
Console.WriteLine("float: {0} double: {1} decimal: {2}", flt, dbl, dcm);
Res...
Change select box option background color
I have a select box and I'm trying to change the background color of the options when the select box has been clicked and shows all the options.
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Add a number to each selection in Sublime Text 2, incremented once per selection
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M represents the step size which will be added to the index for
each selection.
P must be > 0 and will be used to pad the index with
leading zeroes.
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Why is super.super.method(); not allowed in Java?
...hat you can access shadowed variables from superclasses of superclasses by casting this:
interface I { int x = 0; }
class T1 implements I { int x = 1; }
class T2 extends T1 { int x = 2; }
class T3 extends T2 {
int x = 3;
void test() {
System.out.println("x=\t\t" ...
How to filter SQL results in a has-many-through relation
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Results:
Total runtimes from EXPLAIN ANALYZE.
1) Martin 2: 44.594 ms
SELECT s.stud_id, s.name
FROM student s
JOIN student_club sc USING (stud_id)
WHERE sc.club_id IN (30, 50)
GROUP BY 1,2
HAVING COUNT(*) > 1;
2) Erwin 1: 33.217 ms
SELECT s.stud_id, s.name
FROM student s
JOIN ...
Handling warning for possible multiple enumeration of IEnumerable
...ToReadOnly<T>(this IList<T> list) extension method that simple casts if the underlying type supports both interfaces, but you have to add it manually everywhere when refactoring, where as IEnumerable<T> is always compatible.)
As always this is not an absolute, if you're writing da...
How to remove the arrow from a select element in Firefox
I'm trying to style a select element using CSS3. I'm getting the results I desire in WebKit (Chrome / Safari), but Firefox isn't playing nicely (I'm not even bothering with IE). I'm using the CSS3 appearance property, but for some reason I can't shake the drop-down icon out of Firefox.
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