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How to change a nullable column to not nullable in a Rails migration?
I created a date column in a previous migration and set it to be nullable. Now I want to change it to be not nullable. How do I go about doing this assuming there are null rows in that database? I'm ok with setting those columns to Time.now if they're currently null.
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javascript toISOString() ignores timezone offset [duplicate]
... trying to convert Twitter datetime to a local iso-string (for prettyDate) now for 2 days. I'm just not getting the local time right..
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What is the difference between shallow copy, deepcopy and normal assignment operation?
...llow copy:
d = copy.copy(c)
print id(c) == id(d) # False - d is now a new object
print id(c[0]) == id(d[0]) # True - d[0] is the same object as c[0]
Using a deep copy:
d = copy.deepcopy(c)
print id(c) == id(d) # False - d is now a new object
print id(c[0]) == id(d[0]) #...
Best way to add Activity to an Android project in Eclipse?
...n Ubuntu 10.04. When the add dialog comes up, it has two selections... No, now only one "Create a new element at the top level, in Application." Ne;low that there is a text entry field and below that, a box with selections for Activity, Activity Alias, Meta Data and so on. Below that there are butto...
How much is the overhead of smart pointers compared to normal pointers in C++?
...e, and soon shared_ptrs become the default memory management technique. So now you have repeated 1-3% abstraction penalties which are taken over and over again.
– Nathan Doromal
Nov 27 '19 at 14:53
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Difference between
...at you can only read from it and you'll get a T or subclass of T.
super
Now consider List <? super T>.
The wildcard declaration of List<? super Integer> foo3 means that any of these are legal assignments:
List<? super Integer> foo3 = new ArrayList<Integer>(); // Integer...
How do I run a shell script without using “sh” or “bash” commands?
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Hey thanks for your reply. I tried that out. Now I can run it without the "sh" command. But I still have to prefix the command with "./" which I don't want to. :)
– Rameez Hussain
Jan 8 '12 at 18:26
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Should .nuget folder be added to version control?
...uGet 4.x and .NET Standard 2.0, when you use the new csproj format you can now use package references, ironically reintroducing the dependency on msbuild to restore packages, but now packages are a first class citizen of msbuild. The link above also makes mention of the PackageReference, but the fo...
How to create GUID / UUID?
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UUIDs (Universally Unique IDentifier), also known as GUIDs (Globally Unique IDentifier), according to RFC 4122, are identifiers designed to provide certain uniqueness guarantees.
While it is possible to implement an RFC-compliant UUIDs in a few lines of JS (E.g. see @b...
JavaScript - get the first day of the week from current date
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Using the getDay method of Date objects, you can know the number of day of the week (being 0=Sunday, 1=Monday, etc).
You can then subtract that number of days plus one, for example:
function getMonday(d) {
d = new Date(d);
var day = d.getDay(),
diff = d.getDate()...