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Rails: How do I create a default value for attributes in Rails activerecord's model? [duplicate]
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You can set a default option for the column in the migration
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add_column :status, :string, :default => "P"
....
OR
You can use a callback, before_save
class Task < ActiveRecord::Base
before_save :default_values
def default_values...
What's the difference between event.stopPropagation and event.preventDefault?
...k(function () {
alert("parent click event fired!")
})
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div id="foo">
<button id="but">button</button>
</div>
stopPropagation
$("#but").click(function (ev...
Use of def, val, and var in scala
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How can I mark “To Do” comments in Xcode?
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You can use XToDo plugin
https://github.com/trawor/XToDo
use ctrl+t to trigger the List Window on/off
Easy install with alcatraz
use ctrl+t to trigger the List Window on/off
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What is the fastest way to create a checksum for large files in C#
I have to sync large files across some machines. The files can be up to 6GB in size. The sync will be done manually every few weeks. I cant take the filename into consideration because they can change anytime.
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How to convert .pfx file to keystore with private key?
...eUploader: {
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Can you use if/else conditions in CSS?
... use classes for this, if you have access to the HTML. Consider this:
<p class="normal">Text</p>
<p class="active">Text</p>
and in your CSS file:
p.normal {
background-position : 150px 8px;
}
p.active {
background-position : 4px 8px;
}
That's the CSS way to do it.
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Inheritance and Overriding __init__ in python
...eUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 4...
Solving “The ObjectContext instance has been disposed and can no longer be used for operations that
I am trying to populate a GridView using Entity Frameworkm but every time I am getting the following error:
7 Answers
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How to get the first non-null value in Java?
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No, there isn't.
The closest you can get is:
public static <T> T coalesce(T ...items) {
for(T i : items) if(i != null) return i;
return null;
}
For efficient reasons, you can handle the common cases as follows:
public static <T> T coalesce(T a, T ...