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Rank function in MySQL
... (SELECT @curRank := 0) r
ORDER BY age;
The (SELECT @curRank := 0) part allows the variable initialization without requiring a separate SET command.
Test case:
CREATE TABLE person (id int, first_name varchar(20), age int, gender char(1));
INSERT INTO person VALUES (1, 'Bob', 25, 'M');
INSERT I...
How do I speed up the gwt compiler?
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Let's start with the uncomfortable truth: GWT compiler performance is really lousy. You can use some hacks here and there, but you're not going to get significantly better performance.
A nice performance hack you can do is to compile for only specific browsers, by inserting the following line in...
How to encode a URL in Swift [duplicate]
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Swift 4.2
var urlString = originalString.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed)
Swift 3.0
var address = "American Tourister, Abids Road, Bogulkunta, Hyderabad, Andhra Pradesh, India"
let escapedAddress = address.addingPercentEncoding(withAllowedCharacters: Characte...
Check if PHP session has already started
I have a PHP file that is sometimes called from a page that has started a session and sometimes from a page that doesn't have session started. Therefore when I have session_start() on this script I sometimes get the error message for "session already started". For that I've put these lines:
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How can I use pointers in Java?
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All objects in Java are references and you can use them like pointers.
abstract class Animal
{...
}
class Lion extends Animal
{...
}
class Tiger extends Animal
{
public Tiger() {...}
public void growl(){...}
}
Tiger fi...
How do I size a UITextView to its content?
... Tested on iOS 7 to resize an UITextView into an UITableViewCell. Works really great. This is the only answer that finally worked for me. Thanks!
– Alex
Nov 30 '13 at 18:40
39
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How to display all methods of an object?
I want to know how to list all methods available for an object like for example:
8 Answers
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Rename a dictionary key
... this question seems to be asking, is impractical because dict keys are usually immutable objects such as numbers, strings or tuples. Instead of trying to modify the key, reassigning the value to a new key and removing the old key is how you can achieve the "rename" in python.
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Execute code when Django starts ONCE only?
... entirely a separate problem. The idea of special one-time startup before all management commands is hard to understand. You'll have to provide something specific. Perhaps in another question.
– S.Lott
Feb 13 '12 at 12:49
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How do I obtain crash-data from my Android application?
...n? At least when working on my own device being retrieved by cable, but ideally from any instance of my application running on the wild so that I can improve it and make it more solid.
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