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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 end:
User.select(:first,:email).gro...
How do I get jQuery to select elements with a . (period) in their ID?
...wo backslashes before each special character.
A backslash in a jQuery selector escapes the next character. But you need
two of them because backslash is also the escape character for JavaScript
strings. The first backslash escapes the second one, giving you one actual
backslash in your st...
How do I enter RGB values into Interface Builder?
... enter RGB or Hex color values for backgrounds in Interface Builder? I can select predefined colors but I would like to manually enter in RGB values. Where can I do this?
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How to change the blue highlight color of a UITableViewCell?
I'm wondering how to change the blue highlight/selection color of a UITableViewCell , any ideas?
11 Answers
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PHP/MySQL insert row then get 'id'
...);
See mysqli_insert_id().
Whatever you do, don't insert and then do a "SELECT MAX(id) FROM mytable". Like you say, it's a race condition and there's no need. mysqli_insert_id() already has this functionality.
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Get all column names of a DataTable into string array using (LINQ/Predicate)
...es = dt.Columns.Cast<DataColumn>()
.Select(x => x.ColumnName)
.ToArray();
or in LINQ Query syntax:
string[] columnNames = (from dc in dt.Columns.Cast<DataColumn>()
select dc.ColumnName).To...
Visual Studio appears to randomly adopt American keyboard layout
...new Settings app, but there's also an option in the old Region Settings to select a Region for apps that don't support Unicode. For me, this was set to English (UK) even though my only display language is English (Australia).
– rensa
Jul 2 '18 at 4:11
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Could not instantiate class named MKMapView
... project to bring the project settings. Under Targets, click your project, select from the upper toolbar "Build Phases". Under "Link binary With Libraries" tab, you will see the list of frameworks included in your project. Click the "+" button and add MapKit library from the shown list to your proje...
Use images instead of radio buttons
...sibility)
Target the image next to the hidden radio using Adjacent sibling selector +
/* HIDE RADIO */
[type=radio] {
position: absolute;
opacity: 0;
width: 0;
height: 0;
}
/* IMAGE STYLES */
[type=radio] + img {
cursor: pointer;
}
/* CHECKED STYLES */
[type=radio]:checked + img {
...
For loop for HTMLCollection elements
... capability works in Edge 41.16299.15.0 for a nodeList as in document.querySelectorAll(), but not an HTMLCollection as in document.getElementsByClassName() so you have to manually assign the iterator to use it in Edge for an HTMLCollection. It is a total mystery why they'd fix one collection type, ...