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Adding a column to an existing table in a Rails migration
...ontaining line:
add_column :users, email, string
Then do a rake db:migrate and it'll run the new migration, creating the new column.
If you have not yet run the original migration you can just edit it, like you're trying to do. Your migration code is almost perfect: you just need to remove the add_...
How to make return key on iPhone make keyboard disappear?
I have two UITextFields (e.g. username and password) but I cannot get rid of the keyboard when pressing the return key on the keyboard. How can I do this?
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How to stop mongo DB in one command
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Starting and Stopping MongoDB is covered in the MongoDB manual. It explains the various options of stopping MongoDB through the shell, cli, drivers etc. It also details the risks of incorrectly stopping MongoDB (such as data corruptio...
DateTime to javascript date
...ptMilliseconds(DateTime); check in javascript (Press F12 in Google Chrome and go to console) var date = new Date(long); console.log(date.toString());
– Gonen09
Feb 3 at 15:11
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Refreshing OAuth token using Retrofit without modifying all calls
We are using Retrofit in our Android app, to communicate with an OAuth2 secured server. Everything works great, we use the RequestInterceptor to include the access token with each call.
However there will be times, when the access token will expire, and the token needs to be refreshed. When the toke...
Git update submodules recursively
...d submodules may not be updated. In that case, you should also run the command without --init option.
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Java: recommended solution for deep cloning/copying an instance
...ializationUtils - using serialization - if all classes are in your control and you can force implementing Serializable.
Java Deep Cloning Library - using reflection - in cases when the classes or the objects you want to clone are out of your control (a 3rd party library) and you can't make them impl...
String is immutable. What exactly is the meaning? [duplicate]
...ith the fuss of immutability, let's just take a look into the String class and its functionality a little before coming to any conclusion.
This is how String works:
String str = "knowledge";
This, as usual, creates a string containing "knowledge" and assigns it a reference str. Simple enough? Le...
Test if something is not undefined in JavaScript
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response[0] is not defined, check if it is defined and then check for its property title.
if(typeof response[0] !== 'undefined' && typeof response[0].title !== 'undefined'){
//Do something
}
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Scala: what is the best way to append an element to an Array?
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You can use :+ to append element to array and +: to prepend it:
0 +: array :+ 4
should produce:
res3: Array[Int] = Array(0, 1, 2, 3, 4)
It's the same as with any other implementation of Seq.
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