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Clustered vs Non-Clustered
My lower level knowledge of SQL (Server 2008) is limited, and is now being challanged by our DBAs. Let me explain (I have mentioned obvious statements in the hope that I am right, but if you see something wrong, please tell me) the scenario:
...
The best way to remove duplicate values from NSMutableArray in Objective-C?
...ded NSOrderedSet to iOS 5 and Mac OS X 10.7. What had been an algorithm is now two lines of code:
NSOrderedSet *orderedSet = [NSOrderedSet orderedSetWithArray:yourArray];
NSArray *arrayWithoutDuplicates = [orderedSet array];
If you are worried about the order and you're running on iOS 4 or earl...
Variable declared in for-loop is local variable?
...< 5; i++)
{
}
// 'i' is only declared in the method scope now,
// no longer in the child scope -> valid.
i = 4;
// 'i' is declared in the method's scope -> valid.
int A = i;
}
EDIT:
The C# compiler could of course be changed to allow this code to compile ...
Select N random elements from a List in C#
...
@recursive: The proof is almost trivial. We know how to select K items out of K for any K and how to select 0 items out of N for any N. Assume we know a method to uniformly select K or K-1 items out of N-1 >= K; then we can select K items out of N by selecting the fi...
Make Vim show ALL white spaces as a character
...l, in combination with
:set listchars=...
display invisible characters.
Now, there isn't an explicit option which you can use to show whitespace, but in listchars, you could set a character to show for everything BUT whitespace. For example, mine looks like this
:set listchars=eol:$,tab:>-,tr...
EC2 Can't resize volume after increasing size
...
This answer is now deprecated now that AWS supports online resizing for EBS volumes.
– Dale Anderson
Jul 6 '17 at 17:49
...
Error installing mysql2: Failed to build gem native extension
...with-mysql-include="c:\Program Files\MySQL\MySQL Server 5.5\include"'
Now the gem should have installed correctly
Lastly copy the libmysql.dll file from
C:\Program Files\MySQL\MySQL Server 5.5\lib
to
C:\Rails\Ruby1.9.2\bin
--- Install the mysql2 Gem ---
You will now be able to u...
Rails DB Migration - How To Drop a Table?
I added a table that I thought I was going to need, but now no longer plan on using it. How should I remove that table?
22 ...
How many and which are the uses of “const” in C++?
...ect remain the same. Once one of the object changes data, you however need now two versions: One for the original, and one for the copy. That is, you copy on a write to either object, so that they now both have their own version.
Using code:
int main() {
string const a = "1234";
string co...
SPAN vs DIV (inline-block)
...pec, <span> is an inline element and <div> is a block element. Now that can be changed using the display CSS property but there is one issue: in terms of HTML validation, you can't put block elements inside inline elements so:
<p>...<div>foo</div>...</p>
is not...