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mongoDB/mongoose: unique if not null
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As of MongoDB v1.8+ you can get the desired behavior of ensuring unique values but allowing multiple docs without the field by setting the sparse option to true when defining the index. As in:
email : {type: String, trim: true, index: true,...
How do I print the full value of a long string in gdb?
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edited Apr 29 '11 at 21:58
answered Oct 24 '08 at 12:37
Jo...
What's the false operator in C# good for?
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Anton Gogolev
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answered Aug 28 '08 at 21:02
NirNir
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Why does String.split need pipe delimiter to be escaped?
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dlamblindlamblin
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What are some uses of decltype(auto)?
...or is valid. If the function
declarator includes a trailing-return-type (8.3.5), that specifies the declared return type of the function.
If the declared return type of the function contains a placeholder type, the return type of the function is
deduced from return statements in the body of th...
What is Robocopy's “restartable” option?
...rovement of 20MB/s to 600MB/s after removing /z. Source: serverfault.com/a/812212/268224
– user643011
Jun 12 '19 at 6:37
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Can you write nested functions in JavaScript?
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Is this really possible.
Yes.
function a(x) { // <-- function
function b(y) {...
How to use a WSDL file to create a WCF service (not make a call)
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Luke Girvin
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answered Jun 4 '09 at 13:29
marc_smarc_s
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Shell script to delete directories older than n days
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edited Jul 18 '18 at 19:51
tshepang
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Collections.emptyList() returns a List?
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answered Nov 20 '08 at 20:34
InverseFalconInverseFalcon
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