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E11000 duplicate key error index in mongodb mongoose
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The error message is saying that there's already a record with null as the email. In other words, you already have a user without an email address.
The relevant documentation for this:
If a document does not have a value for the indexed field in a unique index, the index will store ...
Windows equivalent to UNIX pwd
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This prints it in the console:
echo %cd%
or paste this command in CMD, then you'll have pwd:
(echo @echo off
echo echo ^%cd^%) > C:\WINDOWS\pwd.bat
share...
Prevent scrolling of parent element when inner element scroll position reaches top/bottom? [duplicat
I have a little "floating tool box" - a div with position:fixed; overflow:auto .
Works just fine.
30 Answers
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How do you make a LinearLayout scrollable?
I have lot of items on the screen and I need to use the scrollbar so the user can scroll down. However, the scroll is either not visible or it's not working. How is it possible to add a scrollbar to a LinearLayout ?
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Convert light frequency to RGB?
... in RGB (bright oranges being a good example) because you cannot "make" arbitrary colours of light by adding three primary colours together, whatever our physics teachers may have told us (well mine did). Too bad, but in practice not usually fatal.
– Francis Davey
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Converting integer to binary in python
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{} places a variable into a string
0 takes the variable at argument position 0
: adds formatting options for this variable (otherwise it would represent decimal 6)
08 formats the number to eight digits zero-padded on the left
b converts the number to its binary representation
If you're using a...
Jackson serialization: ignore empty values (or null)
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You have the annotation in the wrong place - it needs to be on the class, not the field. i.e:
@JsonInclude(Include.NON_NULL) //or Include.NON_EMPTY, if that fits your use case
public static class Request {
// ...
}
As noted in comments, in versions below 2.x the ...
IIS does not list a website that matches the launch url
I need to debug the website i 'm developing (ASP.NET MVC3, Razor, .NET 4, VS2010 SP1
(as administrator)) in IIS7 (Vista Home) and getting the error:
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Animated loading image in picasso
...t seem to support this, only static image drawables. Is there a way to get it working with Picasso or do I have to do something different?
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How to read data when some numbers contain commas as thousand separator?
...ve a csv file where some of the numerical values are expressed as strings with commas as thousand separator, e.g. "1,513" instead of 1513 . What is the simplest way to read the data into R?
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