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How to implement a many-to-many relationship in PostgreSQL?
...ct is hardly unique (not a good "natural key"). Also, enforcing uniqueness and referencing the column in foreign keys is typically cheaper with a 4-byte integer (or even an 8-byte bigint) than with a string stored as text or varchar.
Don't use names of basic data types like date as identifiers. Whi...
Doctrine - How to print out the real sql, not just the prepared statement?
...t, for it to be prepared (this is what is returned by $query->getSql())
And, then, sending the parameters (returned by $query->getParameters())
and executing the prepared statements
This means there is never a "real" SQL query on the PHP side — so, Doctrine cannot display it.
...
How to detect DIV's dimension changed?
...ile performing windows re-sizing, the inner elements may be re-positioned, and the dimension of the div may change. I'm asking if it is possible to hook the div's dimension change event? and How to do that? I currently bind the callback function to the jQuery resize event on the target DIV, however,...
PHP's array_map including keys
...
Not with array_map, as it doesn't handle keys.
array_walk does:
$test_array = array("first_key" => "first_value",
"second_key" => "second_value");
array_walk($test_array, function(&$a, $b) { $a = "$b loves $a"; });
var_dump($tes...
Generate a random letter in Python
Is there a way to generate random letters in Python (like random.randint but for letters)? The range functionality of random.randint would be nice but having a generator that just outputs a random letter would be better than nothing.
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Uncaught ReferenceError: $ is not defined?
...ry-x.x.x.min.js, then jquery-ui-xxxxxx.js.
– Wagner Danda da Silva Filho
Nov 19 '10 at 1:05
27
2 ...
Android: Bitmaps loaded from gallery are rotated in ImageView
...zontal picture even though it appears vertical in the gallery.
Why is that and how can I load it correctly?
19 Answers
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Malloc vs new — different padding
...e picky point. malloc is guaranteed to return an address aligned for any standard type. ::operator new(n) is only guaranteed to return an address aligned for any standard type no larger than n, and if T isn't a character type then new T[n] is only required to return an address aligned for T.
But th...
How to assign colors to categorical variables in ggplot2 that have stable mapping?
...ata frames can become tedious if they are being pulled from separate files and not all factor levels appear in each file.
One way to address this is to create a custom manual colour scale as follows:
#Some test data
dat <- data.frame(x=runif(10),y=runif(10),
grp = rep(LETTERS[1:5],each ...
iPhone - Grand Central Dispatch main thread
I have been using with success, grand central dispatch in my apps, but I was wondering what is the real advantage of using something like this:
...