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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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JavaScript equivalent of PHP’s die
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This will not totally stop execution AFAIK, but only roughly around the throw. Specifics are very blurry but I'm pretty sure the script can keep running somewhere else.
– Rolf
Jan 29 '16 at 10:36
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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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Scheduling recurring task in Android
...leep as soon as your onReceive() method completes. If your alarm receiver called Context.startService(), it is possible that the phone will sleep before the requested service is launched. To prevent this, your BroadcastReceiver and Service will need to implement a separate wake lock policy to ensure...
How do I split a string by a multi-character delimiter in C#?
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This actually returns: 'Th' ' ' ' a sentence' with the example given in the question. Perhaps this is what he actually wants, but it's not what he specified.
– IRBMe
Jul 14 '09 at 17:53
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android button selector
... please elaborate more for how to set pressed and non-pressed state? (with all the components above such as round color, stroke, etc). Many thanks!
– pearmak
Dec 24 '12 at 17:13
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What is a MIME type?
..." the client can go "Ah, this is an HTML document, I can render that internally", while if the server says "This is application/pdf" the client can go "Ah, I need to launch the FoxIt PDF Reader plugin that the user has installed and that has registered itself as the application/pdf handler."
You'll...
Who is “us” and who is “them” according to Git?
...The reason is that Git uses the same merge-engine for rebase, and it's actually cherry-picking your stuff into the upstream branch. us = into, them = from.
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Using varchar(MAX) vs TEXT on SQL Server
...Full Text Index.
LIKE is simpler to implement and is often suitable for small amounts of data, but it has extremely poor performance with large data due to its inability to use an index.
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Having both a Created and Last Updated timestamp columns in MySQL 4.0
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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...