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What is the most efficient way to store tags in a database?
...ic items MUCH more simple. You don't have to create a new tag, remove the allocation of the old one and re-allocate a new one, you just edit the tagname.
For displaying a list of tags, you simply use DISTINCT or GROUP BY, and of course you can count how many times a tag is used easily, too.
...
Android Center text on canvas
...Bounds(Rect) instead. (Do not use Canvas.getClipBounds().getHeight() as it allocates memory for a Rect.)
For reasons of performance, you should allocate objects before they are used in onDraw(). As drawCenter() will be called within onDraw() the object Rect r is preallocated as a field here.
I ...
What is a “cache-friendly” code?
...ilar processors. In some cases, however, it can be worth doing things like allocating a large buffer, and then using only parts of what you allocated to ensure against data sharing the same cache lines (even though you'll probably need to detect the exact processor and act accordingly to do this).
...
Resolve Git merge conflicts in favor of their changes during a pull
...'s, the easiest way is:
git checkout --theirs path/to/the/conflicted_file.php
git add path/to/the/conflicted_file.php
The converse of this (to overwrite the incoming version with your version) is
git checkout --ours path/to/the/conflicted_file.php
git add path/to/the/conflicted_file.php
Surpri...
Real escape string and PDO [duplicate]
...escape_string() with the PDO::quote() method.
Here is an excerpt from the PHP website:
<?php
$conn = new PDO('sqlite:/home/lynn/music.sql3');
/* Simple string */
$string = 'Nice';
print "Unquoted string: $string\n";
print "Quoted string: " . $conn->quote($string) . "\n";...
Sharing a URL with a query string on Twitter
...tion shareOnFB(){
var url = "https://www.facebook.com/sharer/sharer.php?u=https://yoururl.com&t=your message";
window.open(url, '', 'menubar=no,toolbar=no,resizable=yes,scrollbars=yes,height=300,width=600');
return false;
}
function shareOntwitter(){
var url = 'https...
Best practices for in-app database migration for Sqlite
...ng stringWithFormat:@"userdata.sqlite"];
_database = [[FMDatabase alloc] initWithPath:[documentsDir stringByAppendingPathComponent:databaseName]];
_database.logsErrors = YES;
if (![_database openWithFlags:SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE | SQLITE_OPEN_FILEPROTECTI...
capturing self strongly in this block is likely to lead to a retain cycle
...RING YOU TO RETAIN LOOP
}
};
and don't forget to do:
- (void)dealloc {
self.loadingCompletionHandler = NULL;
}
another issue can appear if you will pass weak copy of not retained by anybody object:
MyViewController *vcToGo = [[MyViewCOntroller alloc] init];
__weak MyViewController...
Which C++ idioms are deprecated in C++11?
...eded.
Type Safe Enum Enumerations are very safe in C++11.
Prohibiting heap allocation: The = delete syntax is a much more direct way of saying that a particular functionality is explicitly denied. This is applicable to preventing heap allocation (i.e., =delete for member operator new), preventing co...
How do I increase the RAM and set up host-only networking in Vagrant?
...e.
config.vm.provider "virtualbox" do |vb|
vb.memory = "4096"
end
This allocates about 4GB of RAM to your VM. You can change this according to your requirement. For example, following setting would allocate 2GB of RAM to your VM.
config.vm.provider "virtualbox" do |vb|
vb.memory = "2048"
end
...