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Foreign keys in mongo?
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Ok, but how can I get cource name data from student collection? db.student.find() will return something like courses: [ { course: 'bio101', mark: 85 } ]
– Mark Pegasov
Jun 13 '11 at 18:09
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Replace values in list using Python [duplicate]
...in a comment, i.e.:
what if I had a generator that yields
the values from range(11) instead of a
list. Would it be possible to replace
values in the generator?
Sure, it's trivially easy...:
def replaceiniter(it, predicate, replacement=None):
for item in it:
if predicate(item): yie...
UIGestureRecognizer on UIImageView
...y setting its userInteractionEnabled property to YES. UIImageView inherits from UIView, whose user interaction property is set to YES by default, however, UIImageView's user interaction property is set to NO by default.
From the UIImageView docs:
New image view objects are configured to disrega...
What does the keyword Set actually do in VBA?
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From MSDN:
Set Keyword: In VBA, the Set keyword
is necessary to distinguish between
assignment of an object and assignment
of the default property of the object.
Since default properties are not
supported in V...
How can I send mail from an iPhone application
I want to send an email from my iPhone application. I have heard that the iOS SDK doesn't have an email API. I don't want to use the following code because it will exit my application:
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Return multiple values in JavaScript?
...this table for browser compatibility. Basically, all modern browsers aside from IE support this syntax, but you can compile ES6 code down to IE-compatible JavaScript at build time with tools like Babel.
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How to add pandas data to an existing csv file?
...g and closing your file multiple times, or logging data, statistics, etc.
from contextlib import contextmanager
import pandas as pd
@contextmanager
def open_file(path, mode):
file_to=open(path,mode)
yield file_to
file_to.close()
##later
saved_df=pd.DataFrame(data)
with open_file('y...
How exactly does __attribute__((constructor)) work?
...startup.
That's how all GCC attributes are; presumably to distinguish them from function calls.
GCC-specific syntax.
Yes, this works in C and C++.
No, the function does not need to be static.
The destructor runs when the shared library is unloaded, typically at program exit.
So, the way the constr...
Why does C# have break if it's not optional? [duplicate]
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From the horse's mouth (MSDN) Why is the C# switch statement designed to not allow fall-through, but still require a break?.
Quoting the salient bits, this is why they don't allow fall-through:
This implicit fall-through beh...
Remove DEFINER clause from MySQL Dumps
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The sed command does not remove DEFINER clause from procedures and functions. Here is the enhanced version that handles views, triggers, procedures and functions: sed -e 's/DEFINER[ ]*=[ ]*[^*]*\*/\*/' | sed -e 's/DEFINER[ ]*=[ ]*[^*]*PROCEDURE/PROCEDURE/' | sed -e 's/DE...