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Add a default value to a column through a migration
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Here's how you should do it:
change_column :users, :admin, :boolean, :default => false
But some databases, like PostgreSQL, will not update the field for rows previously created, so make sure you update the field manaully on the migration too.
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Why do I get access denied to data folder when using adb?
... you want to browse everything on your device.
You need to have a phone with root access in order to browse the data folder on an Android phone. That means either you have a developer device (ADP1 or an ION from Google I/O) or you've found a way to 'root' your phone some other way.
You need to be ...
Create instance of generic type in Java?
Is it possible to create an instance of a generic type in Java? I'm thinking based on what I've seen that the answer is no ( due to type erasure ), but I'd be interested if anyone can see something I'm missing:
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Sort a Map by values
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edited Apr 3 '18 at 0:00
community wiki
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Insert picture/table in R Markdown [closed]
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Several sites provide reasonable cheat sheets or HOWTOs for tables and images. Top on my list are:
Pandoc readme, specifically tables
RStudio's RMarkdown, more details in basics (including tables) and a rewrite of pandoc's markdown....
What's the point of Spring MVC's DelegatingFilterProxy?
...hing is a deterministic program.
The DelegatingFilterProxy is a Filter as it was explained above, whose goal is "delegating to a Spring-managed bean that implements the Filter interface", that is, it finds a bean ("target bean" or "delegate") in your Spring application context and invokes it. How i...
input type=“text” vs input type=“search” in HTML5
I'm new to HTML5 as begun to work with HTML5's new form input fields. When I'm working with form input fields, especially <input type="text" /> and <input type="search" /> IMO there wasn't any difference in all major browser including Safari, Chrome, Firefox and Opera. And the search...
How do I choose a HTTP status code in REST API for “Not Ready Yet, Try Again Later”? [closed]
...erver/thingyapi/thingyblob/1234 returns the file (aka "blob") associated with thingy #1234 to download. But it may be that the request is made at a time the file does not exist in the server but most definitely will be available at a later time. There's a batch process in the server that generate...
ASP.NET Web API OperationCanceledException when browser cancels the request
When a user loads a page, it makes one or more ajax requests, which hit ASP.NET Web API 2 controllers. If the user navigates to another page, before these ajax requests complete, the requests are canceled by the browser. Our ELMAH HttpModule then logs two errors for each canceled request:
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Why maven? What are the benefits? [closed]
What are the main benefits of using maven compared to let's say ant ?
It seems to be more of a annoyance than a helpful tool.
I use maven 2, with plain Eclipse Java EE (no m2eclipse), and tomcat.
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