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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...
Remove Object from Array using JavaScript
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This however will remove all the occurrences found, not only the first one
– Flavien Volken
Jul 12 '16 at 6:49
6
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How do you create a Swift Date object?
... dateFromString. If you wanted to return a nil on bad parses, you would ideally use a failible initializer; but you cannot do that now (June 2015), because of a limitation in Swift 1.2, so then you're next best choice is to use a class factory method.
A more elaborate example, which addresses both ...
How to check if std::map contains a key without doing insert?
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Use my_map.count( key ); it can only return 0 or 1, which is essentially the Boolean result you want.
Alternately my_map.find( key ) != my_map.end() works too.
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Python super() raises TypeError
...You have to design any methods that need to multiply-inherit (most notably __init__) to pass through arguments in a clean and sensible way, otherwise you'll get TypeErrors or worse debugging problems when someone tries to multiply-inherit using your class. Unless you've really designed to support MI...
How can I change my Cygwin home folder after installation?
I just installed Cygwin, and it looks like the home directory in the bash prompt is on my Z: drive. That's not where I want it.
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PHP + curl, HTTP POST sample code?
...y simple PHP example that sends a HTTP POST to a remote site
//
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL,"http://www.example.com/tester.phtml");
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS,
"postvar1=value1&postvar2=value2&postvar3=value3");
/...
How do I iterate over a JSON structure? [duplicate]
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Similarly, lodash offers _.forEach (alias _.each for underscore compatibility) to accomplish the same.
– Ville
Oct 25 '14 at 5:29
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Create timestamp variable in bash script
...cial documentation here: https://www.gnu.org/software/coreutils/manual/html_node/Time-conversion-specifiers.html#Time-conversion-specifiers
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Catch Ctrl-C in C
...ote this answer seven years ago. Yes, language standards change. If you really must better the world, please add your new answer but leave mine as is. As the answer has my name on it, I'd prefer it to contain my words too. Thank you.
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