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How do you write a migration to rename an ActiveRecord model and its table in Rails?
...ble_name
end
end
I had to go and rename the model declaration file manually.
Edit:
In Rails 3.1 & 4, ActiveRecord::Migration::CommandRecorder knows how to reverse rename_table migrations, so you can do this:
class RenameOldTableToNewTable < ActiveRecord::Migration
def change
rena...
Entity Framework: There is already an open DataReader associated with this Command
I am using Entity Framework and occasionally i will get this error.
17 Answers
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Modify tick label text
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Caveat: Unless the ticklabels are already set to a string (as is usually the case in e.g. a boxplot), this will not work with any version of matplotlib newer than 1.1.0. If you're working from the current github master, this won't work. I'm not sure what the problem is yet... It may be an ...
ASP.NET MVC: Is Controller created for every request?
...ther controller.
The short version is that ControllerActivator.Create is called (for every request) to create a Controller (which inits a new Controller either through the DependencyResolver or through the Activator if no Resolver has been set up):
public IController Create(RequestContext requestC...
AngularJS error: 'argument 'FirstCtrl' is not a function, got undefined'
...nswered Oct 16 '13 at 15:54
gion_13gion_13
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Why doesn't String switch statement support a null case?
...st by Christian Hujer has some insightful speculation about why null isn't allowed in switches (although it centers on the enum switch rather than the String switch):
Under the hood, the switch statement will typically compile to a tablesswitch byte code. And the "physical" argument to switch as we...
What are the differences between delegates and events?
... the delegate from resetting the delegate and its invocation list and only allows adding or removing targets from the invocation list.
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Python initializing a list of lists [duplicate]
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The problem is that they're all the same exact list in memory. When you use the [x]*n syntax, what you get is a list of n many x objects, but they're all references to the same object. They're not distinct instances, rather, just n references to the sam...
find -exec with multiple commands
...e? this is failing: find ./* -exec grep -v 'COLD,' {} \; -exec egrep -i "my_string" {} \;
– rajeev
Jan 22 '13 at 16:08
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How to read environment variables in Scala
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I would also prefer Properties. It allows to retrieve Optionals, and has names for commonly used properties.
– ppopoff
Dec 17 '15 at 14:46
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