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Run a callback only if an attribute has changed in Rails
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Rails 5.1+
class Page < ActiveRecord::Base
before_save :do_something, if: :will_save_change_to_status_id?
private
def do_something
# ...
end
end
The commit that changed ActiveRecord::Dirty is here: https://github....
Remove textarea inner shadow on Mobile Safari (iPhone)
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341
By adding this css style:
-webkit-appearance: none;
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How to copy an object in Objective-C
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192
As always with reference types, there are two notions of "copy". I'm sure you know them, but f...
Ruby: extend self
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115
It is a convenient way to make instance methods into class methods. But you can also use it as...
Converting string from snake_case to CamelCase in Ruby
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10 Answers
10
Active
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Give all the permissions to a user on a DB
...e other objects, the manual for GRANT has the complete list as of Postgres 12:
privileges on a database object (table, column, view, foreign table, sequence, database, foreign-data wrapper, foreign server, function, procedure, procedural language, schema, or tablespace)
But the rest is rarely ...
How does TransactionScope roll back transactions?
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108
Essentially TransactionScope doesn't track your Adapter's, what it does is it tracks database ...
When should I use ugettext_lazy?
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199
ugettext() vs. ugettext_lazy()
In definitions like forms or models you should use ugettext_la...
Convert SVG to image (JPEG, PNG, etc.) in the browser
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edited May 23 '17 at 12:02
Community♦
111 silver badge
answered Oct 20 '10 at 8:35
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