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How to change the type of a field?
...(x)) and then save the document again.
If you need to do this programmatically and entirely from the shell, you can use the find(...).forEach(function(x) {}) syntax.
In response to the second comment below. Change the field bad from a number to a string in collection foo.
db.foo.find( { 'bad' :...
How do synchronized static methods work in Java and can I use it for loading Hibernate entities?
If I have a util class with static methods that will call Hibernate functions to accomplish basic data access. I am wondering if making the method synchronized is the right approach to ensure thread-safety.
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How can I access and process nested objects, arrays or JSON?
...as any string can be used as key in objects. The key-value pairs are also called the "properties".
Properties can be accessed either using dot notation
const value = obj.someProperty;
or bracket notation, if the property name would not be a valid JavaScript identifier name [spec], or the name is...
Where is SQL Server Management Studio 2012?
... SQL Server 2008 R2 and Visual Studio 2008 and 2010 on my laptop. I've installed SQL Server 2012 and have finally got SQL Server Data Tools to show up, so that I can create SSRS reports in Visual Studio 2010.
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How do I find out which keystore was used to sign an app?
...ture algorithm name: SHA1withRSA
Then use the keytool again to print out all the aliases of your signing keystore:
keytool -list -keystore my-signing-key.keystore
You will get a list of aliases and their certificate fingerprint:
android_key, Jan 23, 2010, PrivateKeyEntry,
Certificate fingerpri...
How to make an OpenGL rendering context with transparent background?
Rendering contexts usually have a solid color on the background (black or whatever, see the image below):
9 Answers
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Markup XML解析库下载(Markup.h 和 Markup.cpp) - 源码下载 - 清泛网 - 专注C/C++及内核技术
... Markup Release 11.1
// Copyright (C) 2009 First Objective Software, Inc. All rights reserved
// Go to www.firstobject.com for the latest CMarkup and EDOM documentation
// Use in commercial applications requires written permission
// This software is provided "as is", with no warranty.
#if !d...
What's the difference between the atomic and nonatomic attributes?
...o are identical; "atomic" is the default behavior (note that it is not actually a keyword; it is specified only by the absence of nonatomic -- atomic was added as a keyword in recent versions of llvm/clang).
Assuming that you are @synthesizing the method implementations, atomic vs. non-atomic chang...
What are the differences between numpy arrays and matrices? Which one should I use?
...ted/numpy.matrix.html
As other answers already state that you can achieve all the operations with NumPy arrays.
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How do you detect/avoid Memory leaks in your (Unmanaged) code? [closed]
... Valgrind for Linux (and OS X). If you use windose - deleaker - best of all!
– John Smith
Dec 12 '11 at 18:12
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