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Oracle PL/SQL - How to create a simple array variable?
... I can't find any collections in Oracle PL/SQL that uses pure memory, they all seem to be associated with tables. I'm looking to do something like this in my PL/SQL (C# syntax):
...
Rails: How do I create a default value for attributes in Rails activerecord's model? [duplicate]
...
add_column :status, :string, :default => "P"
....
OR
You can use a callback, before_save
class Task < ActiveRecord::Base
before_save :default_values
def default_values
self.status ||= 'P' # note self.status = 'P' if self.status.nil? might be safer (per @frontendbeauty)
end
end
...
Why can a function modify some arguments as perceived by the caller, but not others?
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Some answers contain the word "copy" in a context of a function call. I find it confusing.
Python doesn't copy objects you pass during a function call ever.
Function parameters are names. When you call a function Python binds these parameters to whatever objects you pass (via names in a ...
How do I put a clear button inside my HTML text input box like the iPhone does?
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@thebluefox has summarized the most of all. You're only also forced to use JavaScript to make that button to work anyway. Here's an SSCCE, you can copy'n'paste'n'run it:
<!DOCTYPE html>
<html lang="en">
<head>
<title>SO questio...
What are advantages of Artificial Neural Networks over Support Vector Machines? [closed]
...s exactly the number of training samples (though that mainly occurs with small training sets or in degenerate cases) and in general its model size scales linearly. In natural language processing, SVM classifiers with tens of thousands of support vectors, each having hundreds of thousands of features...
How to test Spring Data repositories?
...epositories reasonably for a simple reason: it's way to cumbersome to mock all the parts of the JPA API we invoke to bootstrap the repositories. Unit tests don't make too much sense here anyway, as you're usually not writing any implementation code yourself (see the below paragraph on custom impleme...
Reverse of JSON.stringify?
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JSON.stringify and JSON.parse are almost oposites, and "usually" this kind of thing will work:
var obj = ...;
var json = JSON.stringify(obj);
var obj2 = JSON.parse(json);
so that obj and obj2 are "the same".
However there are some limitations to be aware of.
Often these issues ...
What is more efficient? Using pow to square or just multiply it with itself?
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I tested the performance difference between x*x*... vs pow(x,i) for small i using this code:
#include <cstdlib>
#include <cmath>
#include <boost/date_time/posix_time/posix_time.hpp>
inline boost::posix_time::ptime now()
{
return boost::posix_time::microsec_clock::local_t...
What is the difference between procedural programming and functional programming? [closed]
...
A functional language (ideally) allows you to write a mathematical function, i.e. a function that takes n arguments and returns a value. If the program is executed, this function is logically evaluated as needed.1
A procedural language, on the other ...
OnChange event handler for radio button (INPUT type=“radio”) doesn't work as one value
... It would be better to cache the function outside the loop, so that all radios share the same event handler (now they have identical handlers but they are different functions). Or maybe put all radios inside a wrapper and use event delegation
– Oriol
Aug...