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Rails “validates_uniqueness_of” Case Sensitivity
...validates the uniqueness of 'foo' by asking the DB if that name exists yet and the DB says the name doesn't exist yet.
Process B does the same thing and gets the same response
Process A submits the insert statement for the new record and succeeds
If you have a database constraint requiring uniquenes...
MongoDB atomic “findOrCreate”: findOne, insert if nonexistent, but do not update
as the title says, I want to perform a find (one) for a document, by _id, and if doesn't exist, have it created, then whether it was found or was created, have it returned in the callback.
...
How to get mouse position in jQuery without mouse-events?
...ve there's a way to query the mouse position, but you can use a mousemove handler that just stores the information away, so you can query the stored information.
jQuery(function($) {
var currentMousePos = { x: -1, y: -1 };
$(document).mousemove(function(event) {
currentMousePos.x = ...
Why can templates only be implemented in the header file?
Quote from The C++ standard library: a tutorial and handbook :
17 Answers
17
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How do I get the difference between two Dates in JavaScript?
...uite figure out, however, how to get the difference between the two times, and then how to create a new end Date using that difference.
...
Build query string for System.Net.HttpClient get
...d the query string that
doesn't involve building a name value collection and url encoding
those and then finally concatenating them?
Sure:
var query = HttpUtility.ParseQueryString(string.Empty);
query["foo"] = "bar<>&-baz";
query["bar"] = "bazinga";
string queryString = query.ToStri...
Is Enabling Double Escaping Dangerous?
...ath.
Finally, a very simple, if limited workaround is simply to avoid '+' and use '%20' instead. In any case, using the '+' symbol to encode a space is not valid url encoding, but specific to a limited set of protocols and probably widely supported for backwards-compatibility reasons. If only for...
jQuery SVG, why can't I addClass?
...nstead of .removeClass("newclass")
$("#item").attr("class", "oldclass");
And if you don't want to depend on jQuery:
var element = document.getElementById("item");
// Instead of .addClass("newclass")
element.setAttribute("class", "oldclass newclass");
// Instead of .removeClass("newclass")
element...
Switch statement multiple cases in JavaScript
...one feature of switch ... case. It's too easy to forget a break statement, and if you use fall through intentionally, those forgotten break statements can be very hard to spot. This method lookup version also has lots of great features that switch ... case lacks, such as dynamic extensibility, or t...
Imitate Facebook hide/show expanding/contracting Navigation Bar
...wing property:
@property (nonatomic) CGFloat previousScrollViewYOffset;
And here are the UIScrollViewDelegate methods:
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
CGRect frame = self.navigationController.navigationBar.frame;
CGFloat size = frame.size.height - 21;
CGFloat...