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Ruby on Rails: How do I add a not null constraint to an existing column using a migration?
In my Rails (3.2) app, I have a bunch of tables in my database but I forgot to add a few not null constraints. I've googled around but I can't find how to write a migration which adds not null to an existing column.
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Node.js vs .Net performance
... and able to accommodate large amounts of load. Does anyone have any real world evidence of this vs other frameworks, particularly .Net? Most of the articles i've read are anecdotal or don't have comparisons to .Net.
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Spring MVC @PathVariable with dot (.) is getting truncated
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As far as i know this issue appears only for the pathvariable at the end of the requestmapping.
We were able to solve that by defining the regex addon in the requestmapping.
/somepath/{variable:.+}
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Detect current device with UI_USER_INTERFACE_IDIOM() in Swift
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When working with Swift, you can use the enum UIUserInterfaceIdiom, defined as:
enum UIUserInterfaceIdiom : Int {
case unspecified
case phone // iPhone and iPod touch style UI
case pad // iPad style UI (also include...
Does the 'mutable' keyword have any purpose other than allowing the variable to be modified by a con
... some code that marked a member variable of a class with the mutable keyword. As far as I can see it simply allows you to modify a variable in a const method:
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How to get the current time in Python
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Use:
>>> import datetime
>>> datetime.datetime.now()
datetime.datetime(2009, 1, 6, 15, 8, 24, 78915)
>>> print(datetime.datetime.now())
2009-01-06 15:08:24.789150
And just the time:
>>> datetime.datetime.no...
Clojure: cons (seq) vs. conj (list)
...ap as soon as it grows beyond 9 entries.)
1 Traditionally, in the Lisp world, cons cons(tructs a pair), so Clojure departs from the Lisp tradition in having its cons function construct a seq which doesn't have a traditional cdr. The generalised usage of cons to mean "construct a record of some ty...
Do we need semicolon at the end? [duplicate]
...semicolons in some of the places in my JavaScript, but its not throwing error in any of the browsers. Is the ; at the end needed?
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std::shared_ptr of this
...However while doing some experiments I discovered the following situation for which I could not find a satifying solution:
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SyntaxError: Use of const in strict mode
I'm working with node.js, and in one of my js files I'm using const in "strict mode" . When trying to run it, I'm getting an error:
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