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MongoDB and “joins” [duplicate]
...ll only be evaluated when needed. A join (in a SQL database) on the other hand will resolve relationships and return them as if they were a single table (you "join two tables into one").
You can read more about DBRef here:
http://docs.mongodb.org/manual/applications/database-references/
There are ...
Why does calling a method in my derived class call the base class method?
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There's a difference between new and virtual/override.
You can imagine, that a class, when instantiated, is nothing more than a table of pointers, pointing to the actual implementation of its methods. The following image should visualize this pretty well:
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What's the best way to convert a number to a string in JavaScript? [closed]
...he only conceivable: the number does not care nor know how it was entered, and the standard printed representation is with exactly one digit before the dot.
– Svante
Sep 2 '15 at 18:32
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Is there a way to suppress warnings in Xcode?
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To disable warnings on a per-file basis, using Xcode 3 and llvm-gcc-4.2 you can use:
#pragma GCC diagnostic ignored "-Wwarning-flag"
Where warning name is some gcc warning flag.
This overrides any warning flags on the command line. It doesn't work with all warnings though. ...
How to determine a user's IP address in node
... this call:
request.connection.remoteAddress
See documentation for http and net
EDIT
As @juand points out in the comments, the correct method to get the remote IP, if the server is behind a proxy, is request.headers['x-forwarded-for']
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How do I get the size of a java.sql.ResultSet?
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last() and getRow() aren't static methods in the ResultSet class.
– JeeBee
Oct 10 '08 at 16:21
70
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Change one value based on another value in pandas
I'm trying to reprogram my Stata code into Python for speed improvements, and I was pointed in the direction of PANDAS. I am, however, having a hard time wrapping my head around how to process the data.
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Unable to cast object of type 'System.DBNull' to type 'System.String`
...hat column, the return value is System.DBNull.
– Alexander
May 27 '14 at 7:52
In the first case @Alexander mentions -n...
Use cases for the 'setdefault' dict method
...ld say defaultdict is useful for settings defaults before filling the dict and setdefault is useful for setting defaults while or after filling the dict.
Probably the most common use case: Grouping items (in unsorted data, else use itertools.groupby)
# really verbose
new = {}
for (key, value) in ...
How can I maximize a split window?
...p manual page with split window. I want to maximize the help manual window and close the other window.
11 Answers
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