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How do you write a migration to rename an ActiveRecord model and its table in Rails?
I'm terrible at naming and realize that there are a better set of names for my models in my Rails app. Is there any way to use a migration to rename a model and its corresponding table?
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Compiling a java program into an executable [duplicate]
I've just made a simple program with Eclipse and I want to compile it into an executable, but simply can't seem to find out how to do it.
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Xcode 4 - detach the console/log window
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Go to Xcode preferences, and open the Behavior tab.
Tell Xcode to open a tab called "Debugger" when "Run Pauses" or "Run Starts". Then run it, and break that Debugging tab out into another window (drag it off the tab bar into its own window by just...
Ruby: Easiest Way to Filter Hash Keys?
...t { |key, value| key.to_s.match(/^choice\d+/) }
or you can use delete_if and modify the existing Hash e.g.
params.delete_if { |key, value| !key.to_s.match(/choice\d+/) }
or if it is just the keys and not the values you want then you can do:
params.keys.select { |key| key.to_s.match(/^choice\d+...
Virtual Memory Usage from Java under Linux, too much memory used
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This has been a long-standing complaint with Java, but it's largely meaningless, and usually based on looking at the wrong information. The usual phrasing is something like "Hello World on Java takes 10 megabytes! Why does it need that?" Well, here...
How to test valid UUID/GUID?
...e is the NIL UUID, noted here. The following regex takes this into account and will return a match for a NIL UUID. See below for a UUID which only accepts non-NIL UUIDs. Both of these solutions are for versions 1 to 5 (see the first character of the third block).
Therefore to validate a UUID...
/^...
Google Play on Android 4.0 emulator
How can I install the Google Play .apk onto my Android 4.0 emulator?
8 Answers
8
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Declaring variables inside a switch statement [duplicate]
I saw a few answers to this issue, and I get it — you can't declare and assign variables inside a switch . But I'm wondering if the following is correct at throwing an error saying
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CSS - Expand float child DIV height to parent's height
...ight: 0;
top: 0;
}
Find more detailed results with CSS examples here and more information about equal height columns here.
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Quicksort vs heapsort
Both quicksort and heapsort do in-place sorting. Which is better? What are the applications and cases in which either is preferred?
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