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What is the difference between varchar and varchar2 in Oracle?
...ARCHAR is reserved by Oracle to support distinction between NULL and empty string in future, as ANSI standard prescribes.
VARCHAR2 does not distinguish between a NULL and empty string, and never will.
If you rely on empty string and NULL being the same thing, you should use VARCHAR2.
...
How to link to apps on the app store
...n' s openURL: method to open your item in the App Store.
Sample code:
NSString *iTunesLink = @"itms://itunes.apple.com/app/apple-store/id375380948?mt=8";
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:iTunesLink]];
Swift 4.2
let urlStr = "itms-apps://itunes.apple.com/app/ap...
Best way to add page specific JavaScript in a Rails 3 app?
...ge of the asset pipeline, minified js etc, it's possible to do so and have extra js assets which are combined and only loaded on specific pages by splitting your js into groups which only apply in certain controllers/views/sections of the site.
Move your js in assets into folders, with a separate ...
General guidelines to avoid memory leaks in C++ [closed]
...e heap internally (note the double negation... :-) ...). For example, std::string implemented with Small String Optimization will have a buffer "on the stack of the class" for small strings (~15 chars), and will use a pointer to a memory in the heap for larger strings... But from the outside, std::s...
Java 8 stream reverse order
...g the Collector.of() factory method.
The complete code is this:
Deque<String> output =
input.collect(Collector.of(
ArrayDeque::new,
(deq, t) -> deq.addFirst(t),
(d1, d2) -> { d2.addAll(d1); return d2; }));
The result is a Deque instead of a List, but that ...
Why is Git better than Subversion?
... ways to copy the repo). With Git, that's the default mode anyway. It's an extra command though (git commit commits locally, whereas git push origin master pushes the master branch to the remote named "origin").
As said above: Git adds complexity. Two modes of creating repositories, checkout vs. cl...
ETag vs Header Expires
...s/Cache-control in your headers.
Depending on your needs it may just add extra bytes in your headers which may increase packets which means more TCP overhead. Again, you should see if the overhead of having both things in your headers is necessary or will it just add extra weight in your requests ...
Check if a variable is a string in JavaScript
How can I determine whether a variable is a string or something else in JavaScript?
25 Answers
...
What are attributes in .NET?
...lDescriptionAttribute : Attribute
{
public:
ControlDescriptionAttribute (String ^name, String ^description) :
_name (name),
_description (description)
{
}
property String ^Name
{
String ^get () { return _name; }
}
property String ^Description
{
String ^get () { retu...
Easy pretty printing of floats in python?
...ise numbers, but get rid of trailing zeros for example, use the formatting string %g:
np.set_printoptions(formatter={"float_kind": lambda x: "%g" % x})
For just printing once and not changing global behavior, use np.array2string with the same arguments as above.
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