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Why can't a text column have a default value in MySQL?
...ocs:
Each BLOB or TEXT value is represented internally by a separately allocated object. This is in contrast to all other data types, for which storage is allocated once per column when the table is opened.
It seems like pre-filling these column types would lead to memory usage and performance...
How to find the 'sizeof' (a pointer pointing to an array)?
... which is to stash the size somewhere. For example, if you're dynamically allocating the array, allocate a block one int bigger than the one you need, stash the size in the first int, and return ptr+1 as the pointer to the array. When you need the size, decrement the pointer and peek at the stashe...
String concatenation vs. string substitution in Python
...-squared. Some languages will optimize concatenation to the most recently allocated string, but it's risky to count on the compiler to optimize your quadratic algorithm down to linear. Best to use the primitive (join?) that takes an entire list of strings, does a single allocation, and concatenate...
How to strip HTML tags from a string in SQL Server?
...lowing line in the first block: set @HTMLText = replace(@htmlText, '
',CHAR(13) + CHAR(10))
– Marcello Miorelli
Aug 24 at 11:12
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Mix Razor and Javascript code
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It returns Uncaught SyntaxError: Unexpected token & because the model becomes something like this [{"Id":1,"Name":"Name}]
– Weihui Guo
Feb 4 '19 at 15:33
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Multi-line strings in PHP
...owdoc syntax.
$var is NOT replaced in a nowdoc.
EOD;
Beware that the end token EOD must not be indented at all, or PHP won't acknowledge it. Also, you don't have to use "EOD"; it can be any string you want.
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Change UICollectionViewCell size on different device orientations
...ically in -viewDidLoad
self.portraitLayout = [[UICollectionViewFlowLayout alloc] init];
self.landscapeLayout = [[UICollectionViewFlowLayout alloc] init];
UIInterfaceOrientation orientationOnLunch = [[UIApplication sharedApplication] statusBarOrientation];
if (UIInterfaceOrientationIsPortrait(orie...
Iteration over std::vector: unsigned vs signed index variable
...yClass]’
instantiated from here
dependent-name ‘std::vector<T*,std::allocator<T*> >::iterator’ is parsed as a non-type, but instantiation yields a type
note: say ‘typename std::vector<T*,std::allocator<T*> >::iterator’ if a type is meant
The solution is using the ...
jquery IDs with spaces
...or this is simple, space character is not a valid for ID attribute.
ID tokens must begin with a letter
([A-Za-z]) and may be followed by any
number of letters, digits ([0-9]),
hyphens ("-"), underscores ("_"),
colons (":"), and periods (".").
But if you don't care about standards try $...
What is NSZombie?
...nabled then whenever an object reaches retain count 0, rather than being deallocated it morphs itself into an NSZombie instance. Whenever such a zombie receives a message, it logs a warning rather than crashing or behaving in an unpredictable way. As such, you can debug subtle over-release/autorelea...