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ActiveRecord: size vs count
...l valid.
You'll adapt the function you use depending on your needs.
Basically:
if you already load all entries, say User.all, then you should use length to avoid another db query
if you haven't anything loaded, use count to make a count query on your db
if you don't want to bother with these con...
Does .NET have a way to check if List a contains all items in List b?
...s easy:
public class ListHelper<T>
{
public static bool ContainsAllItems(List<T> a, List<T> b)
{
return !b.Except(a).Any();
}
}
This checks whether there are any elements in b which aren't in a - and then inverts the result.
Note that it would be slightly mo...
How do I check if an index exists on a table field in MySQL?
...name, this way you don't need to find out the index name if it is automatically added without name.
– Programista
Apr 9 '14 at 11:05
...
“The given path's format is not supported.”
...spaces; 'System.IO.Path' is a type not a namespace
– All Blond
Sep 8 '11 at 13:32
2
@All Blond pu...
Modulo operation with negative numbers
...
C99 requires that when a/b is representable:
(a/b) * b + a%b shall equal a
This makes sense, logically. Right?
Let's see what this leads to:
Example A. 5/(-3) is -1
=> (-1) * (-3) + 5%(-3) = 5
This can only happen if 5%(-3) is 2.
Example B. (-5)/3 is -1
=> (-1) * 3 + (-5...
How to return PDF to browser in MVC?
... document.Open();
// Set up fonts used in the document
Font font_heading_1 = FontFactory.GetFont(FontFactory.TIMES_ROMAN, 19, Font.BOLD);
Font font_body = FontFactory.GetFont(FontFactory.TIMES_ROMAN, 9);
// Create the heading paragraph with the headig font
Paragraph paragraph...
Cell spacing in UICollectionView
...
This is a much better answer. Take a look at the callbacks you can adjust in the UICollectionViewDelegateFlowLayout and you can see how this can be tweaked.
– cynistersix
Dec 17 '14 at 2:52
...
How to capture Curl output to a file?
...if an old one exists).
curl -K myconfig.txt >> output.txt
Appends all output you receive to the specified file.
Note: The -K is optional.
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Why doesn't Java allow to throw a checked exception from static initialization block?
Why doesn't Java allow to throw a checked exception from a static initialization block? What was the reason behind this design decision?
...
jQuery.inArray(), how to use it right?
...
The right way of using inArray(x, arr) is not using it at all, and using instead arr.indexOf(x).
The official standard name is also more clear on the fact that the returned value is an index thus if the element passed is the first one you will get back a 0 (that is falsy in Javascr...