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Set value to NULL in MySQL
... can be inserted/updated without quotes:
INSERT INTO user (name, something_optional) VALUES ("Joe", NULL);
UPDATE user SET something_optional = NULL;
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How to Create Deterministic Guids
... brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 4...
How to find and return a duplicate value in array
...ou're writing this code for some huge scaling data (and if so, you can actually just use C or Python), the provided answer is far more elegant/readable, and isnt' going to run that much slower compared to a linear time solution. furthermore, in theory, the linear time solution requires linear space,...
How do you send a HEAD HTTP request in Python 2?
...rt urllib2
>>> class HeadRequest(urllib2.Request):
... def get_method(self):
... return "HEAD"
...
>>> response = urllib2.urlopen(HeadRequest("http://google.com/index.html"))
Headers are available via response.info() as before. Interestingly, you can find the URL th...
Interfaces with static fields in java for sharing 'constants'
...
It's generally considered bad practice. The problem is that the constants are part of the public "interface" (for want of a better word) of the implementing class. This means that the implementing class is publishing all of these val...
Python: Find in list
...e which suffers from inaccuracy.
As for your second question: There's actually several possible ways if "finding" things in lists.
Checking if something is inside
This is the use case you describe: Checking whether something is inside a list or not. As you know, you can use the in operator for th...
Best way to do Version Control for MS Excel
...lution here.
The solution for me was to create a spreadsheet that exports all modules on save, and removes and re-imports the modules on open. Yes, this could be potentially dangerous for converting existing spreadsheets.
This allows me to edit the macros in the modules via Emacs (yes, emacs) or n...
How do I declare an array of weak references in Swift?
...T] {
return objects.flatMap { $0.object }
}
func contains(_ object: T) -> Bool {
return self.objects.contains(WeakObject(object: object))
}
func addObject(_ object: T) {
self.objects.formUnion([WeakObject(object: object)])
}
func addObjects(_ obj...
config.assets.compile=true in Rails production, why not?
The default Rails app installed by rails new has config.assets.compile = false in production.
7 Answers
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New self vs. new static
...the first method, whereas static is bound to the called class (also see get_called_class()).
class A {
public static function get_self() {
return new self();
}
public static function get_static() {
return new static();
}
}
class B extends A {}
echo get_class(B::ge...