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mongodb group values by multiple fields
... $slice just off the basic aggregation result. For "large" results, run parallel queries instead for each grouping ( a demonstration listing is at the end of the answer ), or wait for SERVER-9377 to resolve, which would allow a "limit" to the number of items to $push to an array.
db.books.aggregate(...
How much faster is Redis than mongoDB?
...benchmarks that test your case and link from this post instead, then we'll all benefit from your "tested" opinion.
– Homer6
Jan 7 '13 at 18:38
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How do I install cygwin components from the command line?
... the Cygwin package similar to apt-get on Debian or yum on redhat that allows me to install components from the command line?
...
Is there a Python equivalent of the C# null-coalescing operator?
In C# there's a null-coalescing operator (written as ?? ) that allows for easy (short) null checking during assignment:
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Linq to Sql: Multiple left outer joins
...
This may be cleaner (you dont need all the into statements):
var query =
from order in dc.Orders
from vendor
in dc.Vendors
.Where(v => v.Id == order.VendorId)
.DefaultIfEmpty()
from status
in dc.Status
.Where(...
Best general SVN Ignore Pattern?
...gardless of whether it is listed in the global ignore pattern or not. Generally you do not want *.dll being tracked by SVN however you can always explicitly add any necessary ones (which I often do in the case of third-party assemblies).
– Zach Burlingame
Apr 8...
Calling dynamic function with dynamic number of parameters [duplicate]
I’m looking for a trick about this. I know how to call a dynamic, arbitrary function in JavaScript, passing specific parameters, something like this:
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phonegap open link in browser
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As suggested in a similar question, use JavaScript to call window.open with the target argument set to _system, as per the InAppBrowser documentation:
<a href="#" onclick="window.open('http://www.kidzout.com', '_system'); return false;">www.kidzout.com</a>
This sho...
Detecting Unsaved Changes
...reunload methods as required.
From the comments, the following references all input fields, without duplicating code:
$(':input').change(function () {
Using $(":input") refers to all input, textarea, select, and button elements.
...
Dealing with commas in a CSV file
...any easily-available csv library - that is to say RFC 4180.
There's actually a spec for CSV format and how to handle commas:
Fields containing line breaks (CRLF), double quotes, and commas should be enclosed in double-quotes.
http://tools.ietf.org/html/rfc4180
So, to have values foo and ...