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MySQL: Fastest way to count number of rows
...mysql side?
If the COUNT(*) is slow, you should run EXPLAIN on the query, and check if indexes are really used, and where should they be added.
The following is not the fastest way, but there is a case, where COUNT(*) doesn't really fit - when you start grouping results, you can run into problem...
How do you tell if caps lock is on using JavaScript?
...s/edit?js,output
Also, here is a modified version (can someone test on mac and confirm)
NEW VERSION: https://jsbin.com/xiconuv/edit?js,output
NEW VERSION:
function isCapslock(e) {
const IS_MAC = /Mac/.test(navigator.platform);
const charCode = e.charCode;
const shiftKey = e.shiftKey;
if (...
Simple (non-secure) hash function for JavaScript? [duplicate]
... can simply call .hashCode() on any string, e.g. "some string".hashCode(), and receive a numerical hash code (more specifically, a Java equivalent) such as 1395333309.
String.prototype.hashCode = function() {
var hash = 0;
if (this.length == 0) {
return hash;
}
for (var i =...
What is the AppDelegate for and how do I know when to use it?
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I normally avoid the design approach implied by Andrew's use of the term "heart of your application". What I mean by this is that I think you should avoid lumping too many things in a central location -- good program design normally involves separating functionality by "ar...
Can I find events bound on an element with jQuery?
I bind two event handlers on this link:
9 Answers
9
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Bordered UITextView
... I didn't think it really needed much explaining, view is the UITextView, and the code goes wherever you'd set up the view (awakeFromNib or viewDidLoad are two possible places). Since there was no code given there's no way to give good context in response.
– Kendall Helmstett...
Setup RSpec to test a gem (not Rails)
... used Bundler ( bundle gem my_gem ) to setup the structure for the new gem and edit the *.gemspec manually.
I also added s.add_development_dependency "rspec", ">= 2.0.0" to gemspec and did a bundle install .
...
Bind TextBox on Enter-key press
The default databinding on TextBox is TwoWay and it commits the text to the property only when TextBox lost its focus.
...
How to access the last value in a vector?
... vector that is nested in a dataframe one or two levels. Is there a quick and dirty way to access the last value, without using the length() function? Something ala PERL's $# special var?
...
Clean code to printf size_t in C++ (or: Nearest equivalent of C99's %z in C++)
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Most compilers have their own specifier for size_t and ptrdiff_t arguments, Visual C++ for instance use %Iu and %Id respectively, I think that gcc will allow you to use %zu and %zd.
You could create a macro:
#if defined(_MSC_VER) || defined(__MINGW32__) //__MINGW32__ should...