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Adding a column to an existing table in a Rails migration
...cord::Migration[5.0]
def change
end
end
In that case you have to manually an add_column to change:
class AddEmailToUsers < ActiveRecord::Migration[5.0]
def change
add_column :users, :email, :string
end
end
And then run rake db:migrate
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Having both a Created and Last Updated timestamp columns in MySQL 4.0
...:
Previously, at most one TIMESTAMP column per table could be automatically initialized or updated to the current date and time. This restriction has been lifted. Any TIMESTAMP column definition can have any combination of DEFAULT CURRENT_TIMESTAMP and ON UPDATE CURRENT_TIMESTAMP clauses. In add...
Is it possible to make a Tree View with Angular?
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I was really tired of people constantly commenting on this that the URL has my name in it ( and therefore it is plagiarism! ). That is unfortunately how jsfiddle works. If you fork something while you are logged in it retains your us...
How exactly to use Notification.Builder
...n.Builder(ctx);
builder.setContentIntent(contentIntent)
.setSmallIcon(R.drawable.some_img)
.setLargeIcon(BitmapFactory.decodeResource(res, R.drawable.some_big_img))
.setTicker(res.getString(R.string.your_ticker))
.setWhen(System.currentTimeMillis())
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What are the disadvantages to declaring Scala case classes?
...immutable data structures, case classes appear to be a godsend, giving you all of the following for free with just one keyword:
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Choose between ExecutorService's submit and ExecutorService's execute
...g the task to be invoked. The default UncaughtExceptionHandler, which typically prints the Throwable stack trace to System.err, will be invoked if no custom handler has been installed.
On the other hand, a Throwable generated by a task queued with submit() will bind the Throwable to the Future that...
Find index of last occurrence of a sub-string using T-SQL
...ence of a string using SQL? I am using SQL Server 2000 right now. I basically need the functionality that the .NET System.String.LastIndexOf method provides. A little googling revealed this - Function To Retrieve Last Index - but that does not work if you pass in a "text" column expression. ...
Uses for the Java Void Reference Type?
...ce type . The only situation I have ever seen it used is to parameterize Callable s
11 Answers
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How do I put a variable inside a string?
...avefig('hanning(%d).pdf' % num)
The % operator, when following a string, allows you to insert values into that string via format codes (the %d in this case). For more details, see the Python documentation:
https://docs.python.org/3/library/stdtypes.html#printf-style-string-formatting
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How to get document height and width without using jquery
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You should use getBoundingClientRect as it usually works cross browser and gives you sub-pixel precision on the bounds rectangle.
elem.getBoundingClientRect()
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