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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...
How to install a gem or update RubyGems if it fails with a permissions error
I'm trying to install a gem using gem install mygem or update RubyGems using gem update --system , and it fails with this error:
...
Determine device (iPhone, iPod Touch) with iOS
...
@AnilSivadas: UI_USER_INTERFACE_IDIOM() is safe to use in apps that still support iOS < 3.2: it is a macro in UIDevice.h specifically written to default to UIUserInterfaceIdiomPhone on such older iOS versions.
– mkle...
How can one print a size_t variable portably using the printf family?
...on is to cast your variables to unsigned long long and use %llu to be maximally portable.
– Adam Rosenfield
Apr 13 '10 at 1:52
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show 12 mor...
Hidden features of Ruby
...
From Ruby 1.9 Proc#=== is an alias to Proc#call, which means Proc objects can be used in case statements like so:
def multiple_of(factor)
Proc.new{|product| product.modulo(factor).zero?}
end
case number
when multiple_of(3)
puts "Multiple of 3"
when multiple...
How do I check if a given string is a legal/valid file name under Windows?
...than ASCII space)
Any other character that the target file system does not allow (say, trailing periods or spaces)
Any of the DOS names: CON, PRN, AUX, NUL, COM0, COM1, COM2, COM3, COM4, COM5, COM6, COM7, COM8, COM9, LPT0, LPT1, LPT2, LPT3, LPT4, LPT5, LPT6, LPT7, LPT8, LPT9 (and avoid AUX.txt, etc)...
How to set cookie in node js using express framework?
...important!
});
// let static middleware do its job
app.use(express.static(__dirname + '/public'));
Also, middleware needs to either end a request (by sending back a response), or pass the request to the next middleware. In this case, I've done the latter by calling next() when the cookie has been...
How to ssh to vagrant without actually running “vagrant ssh”?
...sh" because it's -c option didn't pass on arguments properly. This is basically what it does (there might be more, but it works fine this way)
#!/bin/sh
PORT=$(vagrant ssh-config | grep Port | grep -o '[0-9]\+')
ssh -q \
-o UserKnownHostsFile=/dev/null \
-o StrictHostKeyChecking=no \
-i...
How to retrieve GET parameters from javascript? [duplicate]
...%2Fadmin
EDIT: I took the liberty of changing Qwerty's answer, which is really good, and as he pointed I followed exactly what the OP asked:
function findGetParameter(parameterName) {
var result = null,
tmp = [];
location.search
.substr(1)
.split("&")
.f...
Android Facebook integration with invalid key hash
...eason. I have also got the same problem. So I tried it through programmatically.
Follow these steps:
Paste the following code in oncreate().
try {
PackageInfo info = getPackageManager().getPackageInfo(
"com.example.packagename",
PackageMan...