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What's the difference between VARCHAR and CHAR?
...n hold is 255 characters.
It's 50% faster than VARCHAR.
Uses static memory allocation.
VARCHAR
Used to store variable length alphanumeric data.
The maximum this data type can hold is up to
Pre-MySQL 5.0.3: 255 characters.
Post-MySQL 5.0.3: 65,535 characters shared for the row.
It's slower tha...
How to check if remote branch exists on a given remote repository?
...ote --heads https://github.com/rails/rails.git
5b3f7563ae1b4a7160fda7fe34240d40c5777dcd refs/heads/1-2-stable
81d828a14c82b882e31612431a56f830bdc1076f refs/heads/2-0-stable
b5d759fd2848146f7ee7a4c1b1a4be39e2f1a2bc refs/heads/2-1-stable
c6cb5a5ab00ac9e857e5b2757d2bce6a5ad14b32 refs/heads/...
YAML current date in rmarkdown
...l::yaml.load(front_matter) :
Scanner error: while scanning for the next token at line 3, column 31
found character that cannot start any token at line 3, column 31
Calls: <Anonymous> ... output_format_from_yaml_front_matter ->
parse_yaml_front_matter -> <Anonymous> ->...
boost::flat_map and its performance compared to map and unordered_map
... few variations of the scenario.
A container performance is affected by:
Allocator
size of contained type
cost of implementation of copy operation, assignment operation, move operation, construction operation, of the contained type.
number of elements in the container (size of the problem)
type ha...
How to find a Java Memory Leak
...t "TRACE nnnn" to see the top few frames of the stack where the object was allocated. Often, once I see where the object is allocated, I find a bug and I'm done. Also, note that you can control how many frames are recorded in the stack with the options to -Xrunhprof.
If you check out the allocation...
Check list of words in another string [duplicate]
...f
Of course you can also do whole word matches with regex using the "\b" token.
The performance of these and Kenny's solution are going to depend on several factors, such as how long the word list and phrase string are, and how often they change. If performance is not an issue then go for the si...
Converting milliseconds to a date (jQuery/JavaScript)
...g( now.customFormat( "#DD#/#MM#/#YYYY# #hh#:#mm#:#ss#" ) );
Here are the tokens supported:
token: description: example:
#YYYY# 4-digit year 1999
#YY# 2-digit year 99
#MMMM# full month name February
#MMM# 3-letter month name ...
How to create local notifications?
...n *)notification {
UIAlertView *notificationAlert = [[UIAlertView alloc] initWithTitle:@"Notification" message:@"This local notification"
delegate:nil cancelButtonTitle:@"Ok" otherButtonTitles:nil, nil];
[notificationAlert show];
// NSLog(@"didReceiveLocalNotific...
iOS: Compare two dates
...STimeInterval distance
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"dd/MM/yyyy"];
[dateFormatter setLocale:[[[NSLocale alloc] initWithLocaleIdentifier:@"en_US"]
autorelease]];
NSString *stringDate = [dateFormatter stringF...
Is the pImpl idiom really used in practice?
... create a structure for the private objects of a class and dynamically allocate them to decrease the compilation time (and also hide the private implementations in a better manner).
...