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How to search in array of object in mongodb
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Use $elemMatch to find the array of particular object
db.users.findOne({"_id": id},{awards: {$elemMatch: {award:'Turing Award', year:1977}}})
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How do I concatenate two strings in C?
...-terminator.
char* concat(const char *s1, const char *s2)
{
const size_t len1 = strlen(s1);
const size_t len2 = strlen(s2);
char *result = malloc(len1 + len2 + 1); // +1 for the null-terminator
// in real code you would check for errors in malloc here
memcpy(result, s1, len1);
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What are the options for storing hierarchical data in a relational database? [closed]
...s a result, most people end up having to settle for one or the other especially if there are more than, say, a lousy 100,000 nodes or so. Using the push stack method can take a whole day to do the conversion on what MLM'ers would consider to be a small million node hierarchy.
I thought I'd give Ce...
What does cherry-picking a commit with Git mean?
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This is in contrast with other ways such as merge and rebase which normally apply many commits onto another branch.
Make sure you are on the branch you want to apply the commit to.
git checkout master
Execute the following:
git cherry-pick <commit-hash>
N.B.:
If you cherry-pick f...
What's the maximum value for an int in PHP?
Ignoring the special libraries that allow you to work with very big numbers, what's the largest int value you can store in PHP?
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How to log out user from web site using BASIC authentication?
...designed to manage logging out. You can do it, but not completely automatically.
What you have to do is have the user click a logout link, and send a ‘401 Unauthorized’ in response, using the same realm and at the same URL folder level as the normal 401 you send requesting a login.
They must b...
How to fix getImageData() error The canvas has been tainted by cross-origin data?
...the remote server sets the following header appropriately:
Access-Control-Allow-Origin "*"
The Dropbox file chooser when using the "direct link" option is a great example of this. I use it on oddprints.com to hoover up images from the remote dropbox image url, into my canvas, and then submit the ...
How to programmatically take a screenshot on Android?
... save the file:
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
And this is the code (running in an Activity):
private void takeScreenshot() {
Date now = new Date();
android.text.format.DateFormat.format("yyyy-MM-dd_hh:mm:ss", now);
try {
//...
Is there a VB.NET equivalent for C#'s '??' operator?
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If Operator (Visual Basic)
Uses short-circuit evaluation to conditionally return one of two
values. The If operator can be called with three arguments or with two
arguments.
If( [argument1,] argument2, argument3 )
If Operator Called with Two Arguments
The first argument to If...
EF Code First: How do I see 'EntityValidationErrors' property from the nuget package console?
...pper function in the Configuration class in the Seed method, and replaced calls to SaveChanges with calls to my function instead. This function would simply enumerate the errors within the EntityValidationErrors collection, and rethrow an exception where the Exception message lists the individual p...