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mongoDB/mongoose: unique if not null
...ngoDB v1.8+ you can get the desired behavior of ensuring unique values but allowing multiple docs without the field by setting the sparse option to true when defining the index. As in:
email : {type: String, trim: true, index: true, unique: true, sparse: true}
Or in the shell:
db.users.ensureIn...
Upgrading PHP in XAMPP for Windows?
...a backup of your htdocs and data folder (subfolder of MySQL folder), reinstall upgraded version and replace those folders.
Note:
In case you have changed config files like PHP (php.ini), Apache (httpd.conf) or any other, please take back up of those files as well and replace them with newly install...
What is a Manifest in Scala and when do you need it?
Since Scala 2.7.2 there is something called Manifest which is a workaround for Java's type erasure. But how does Manifest work exactly and why / when do you need to use it?
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Maven command to determine which settings.xml file Maven is using
...utput until maven 3 was released, but your post some 2.5 years later is finally the exact answer I was looking for (sorry for the 6 month delay in noticing it).
– harschware
Nov 12 '12 at 17:25
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Notification passes old Intent Extras
...gIntent contentIntent = PendingIntent.getActivity(context, UNIQUE_INT_PER_CALL, notificationIntent, 0);
intents are not created if you send the same params. They are reused.
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What is the difference between Pan and Swipe in iOS?
...esture is continuous. It begins (began) when the minimum number of fingers allowed (minimumNumberOfTouches) has moved enough to be considered a pan. It changes (changed) when a finger moves while at least the minimum number of fingers are pressed down. It ends (ended) when all fingers are lifted.
C...
What is the difference between 'my' and 'our' in Perl?
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On the other hand, our variables are package variables, and thus automatically:
global variables
definitely not private
not necessarily new
can be accessed outside the package (or lexical scope) with the
qualified namespace, as $package_name::variable.
Declaring a variable with our allows you...
Android static object lifecycle
...cation?
The OS starts a process and assigns it a unique process id and allocates a process table.A process start an instance of DVM(Dalvik VM); Each application runs inside a DVM.
A DVM manages class loading unloading, instance lifecycle, GC etc.
Lifetime of a static variable: A static variable...
What is the purpose of the “Prefer 32-bit” setting in Visual Studio and how does it actually work?
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Microsoft has a blog entry What AnyCPU Really Means As Of .NET 4.5 and Visual Studio 11:
In .NET 4.5 and Visual Studio 11 the cheese has been moved. The
default for most .NET projects is again AnyCPU, but there is more than
one meaning to AnyCPU now. There i...
Why use strict and warnings?
...tify how much it helps. It should suffice to say that they help unconditionally.
– ikegami
Nov 6 '11 at 19:42
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