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E11000 duplicate key error index in mongodb mongoose
... null value.
In other words, a sparse index is ok with multiple documents all having null values.
sparse indexes
From comments:
Your error says that the key is named mydb.users.$email_1 which makes me suspect that you have an index on both users.email and users.local.email (The former being old an...
What is the difference between MOV and LEA?
...reas MOV loads the actual value at that address.
The purpose of LEA is to allow one to perform a non-trivial address calculation and store the result [for later usage]
LEA ax, [BP+SI+5] ; Compute address of value
MOV ax, [BP+SI+5] ; Load value at that address
Where there are just constants invo...
Python memory leaks [closed]
... have a long-running script which, if let to run long enough, will consume all the memory on my system.
9 Answers
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How do I efficiently iterate over each entry in a Java Map?
...erret The only reason you might want to use an iterator is if you need to call its remove method. If that is the case, this other answer shows you how to do it. Otherwise, the enhanced loop as shown in the answer above is the way to go.
– assylias
Oct 8 '12 at ...
What’s the difference between ScalaTest and Scala Specs unit test frameworks?
...calaTest, and that I think reflects a difference in design attitude. I actually cut probably 2/3 of the matcher syntax I built and considered for release. I will add more matchers in future releases, but wanted to be sure I knew users actually wanted something before I added it. However ScalaTest's ...
How to add text inside the doughnut chart using Chart.js?
...ext based off the amount of text and the size of the doughnut. Here is a small script you can use to dynamically place any amount of text in the middle, and it will automatically resize it.
Example: http://jsfiddle.net/kdvuxbtj/
It will take any amount of text in the doughnut sized perfect for ...
Error: Could not find or load main class in intelliJ IDE
...ginner in Java and am trying to run my code using IntelliJ that I just installed as my IDE with JDK 1.7. The following piece of code keeps does not even compile and keeps giving me the error:
...
iOS 7 style Blur view
...bove, I recently reworked the blurs in GPUImage to support variable radii, allowing for the complete replication of the blur size in iOS 7's control center view. From that, I created the GPUImageiOS7BlurFilter class that encapsulates the proper blur size and color correction that Apple appears to be...
项目管理实践【五】自动编译和发布网站【Using Visual Studio with Source ...
...om/download/f/d/0/fd05def7-68a1-4f71-8546-25c359cc0842/UtilitySpotlight2006_11.exe
安装完成后，就开始今天的教程了。
我们以前面教程中创建的StartKit解决方案为例子，结构如下：
在上图所示的Web项目StartKit上右键点击，然后点击Add Web Deploymen...
How to find out where a function is defined?
...
@EHerman I don't think you can find callers of a function with reflection. If you could it probably wouldn't work well for this because PHP files tend to be included on demand, and so you would likely not have all the code loaded which does call the function.
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