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Find rows with multiple duplicate fields with Active Record, Rails & Postgres
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Tested & Working Version
User.select(:first,:email).group(:first,:email).having("count(*) > 1")
Also, this is a little unrelated but handy. If you want to see how times each combination was found, put .size at the e...
Get second child using jQuery
...jsperf.com/second-child-selector
The $(t).first().next() method is the fastest here, by far.
But, on the other hand, if you take the <tr> node and find the <td> children and and run the same test, the results won't be the same.
Hope it helps. :)
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How do I deep copy a DateTime object?
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I haven't tested it actually, but it is mentioned at php.net that this is only aviable for PHP 5.3 and greater.
– hugo der hungrige
Feb 1 '13 at 1:02
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Passing data to a bootstrap modal
... make this work using jQuery's .on event handler.
Here's a fiddle you can test; just make sure to expand the HTML frame in the fiddle as much as possible so you can view the modal.
http://jsfiddle.net/Au9tc/605/
HTML
<p>Link 1</p>
<a data-toggle="modal" data-id="ISBN564541" title...
Youtube iframe wmode issue
...=opaque to the URL seems to solve this problem for me, although I have not tested it in IE yet.
For those of you having troubles with the previously proposed solution, note that an inital ampersand will only work if you are already supplying other arguments to the URL. The first argument must have ...
Is it a good practice to use try-except-else in Python?
...ns inherent in some of the "look-before-you-leap" constructs. For example, testing os.path.exists results in information that may be out-of-date by the time you use it. Likewise, Queue.full returns information that may be stale. The try-except-else style will produce more reliable code in these ca...
How to export JavaScript array info to csv (on client side)?
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Based on the answers above I created this function that I have tested on IE 11, Chrome 36 and Firefox 29
function exportToCsv(filename, rows) {
var processRow = function (row) {
var finalVal = '';
for (var j = 0; j < row.length; j++) {
var innerValue ...
Java array reflection: isArray vs. instanceof
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In most cases, you should use the instanceof operator to test whether an object is an array.
Generally, you test an object's type before downcasting to a particular type which is known at compile time. For example, perhaps you wrote some code that can work with a Integer[] or an i...
Is the primary key automatically indexed in MySQL?
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I guess this is the answer
mysql> create table test(id int primary key, s varchar(20));
Query OK, 0 rows affected (0.06 sec)
mysql> show indexes from test \G
*************************** 1. row ***************************
Table: test
Non_unique: 0
Key_n...
Check if a string has white space
...hasWhiteSpace(s) {
return s.indexOf(' ') >= 0;
}
Or you can use the test method, on a simple RegEx:
function hasWhiteSpace(s) {
return /\s/g.test(s);
}
This will also check for other white space characters like Tab.
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