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What's the difference between comma separated joins and join on syntax in MySQL? [duplicate]
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There is no difference at all.
Second representation makes query more readable and makes it look very clear as to which join corresponds to which condition.
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How to print struct variables in console?
... @fnr If you have a JSON document, you would need to unmarshall it, before being able to print its field.
– VonC
Jul 1 '14 at 14:16
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How to get the file extension in PHP? [duplicate]
...omething that's actually designed for what you want: pathinfo():
$path = $_FILES['image']['name'];
$ext = pathinfo($path, PATHINFO_EXTENSION);
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How do I use reflection to invoke a private method?
There are a group of private methods in my class, and I need to call one dynamically based on an input value. Both the invoking code and the target methods are in the same instance. The code looks like this:
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Declare a block method parameter without using a typedef
...ssue benefits from multiple):
@implementation CallbackAsyncClass {
void (^_loginCallback) (NSDictionary *response);
}
// …
- (void)loginWithCallback:(void (^) (NSDictionary *response))handler {
// Do something async / call URL
_loginCallback = Block_copy(handler);
// response will c...
Programmatically saving image to Django ImageField
...import File # you need this somewhere
import urllib
# The following actually resides in a method of my model
result = urllib.urlretrieve(image_url) # image_url is a URL to an image
# self.photo is the ImageField
self.photo.save(
os.path.basename(self.url),
File(open(result[0], 'rb'))
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Pros and Cons of Interface constants [closed]
...mple of a good enough and a bad use:
Bad:
interface User {
const TYPE_ADMINISTRATOR = 1;
const TYPE_USER = 2;
const TYPE_GUEST = 3;
}
Good Enough:
interface HTTPRequest_1_1 {
const TYPE_CONNECT = 'connect';
const TYPE_DELETE = 'delete';
const TYPE_GET ...
How do I set bold and italic on UILabel of iPhone/iPad?
...t {
return with([.traitBold, .traitItalic])
}
func with(_ traits: UIFontDescriptor.SymbolicTraits...) -> UIFont {
guard let descriptor = self.fontDescriptor.withSymbolicTraits(UIFontDescriptor.SymbolicTraits(traits).union(self.fontDescriptor.symbolicTraits)) else {
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Is there a way to perform “if” in python's lambda
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If you still want to print you can import future module
from __future__ import print_function
f = lambda x: print(x) if x%2 == 0 else False
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How do you use variables in a simple PostgreSQL script?
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This doesn't answer the question at all. In MS SQL you can define a var in a query and use it right there, in the same tool. I don't get why people keep proposing this as an answer, in every version of this question.
– stone
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