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Foreign Key to multiple tables
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You have a few options, all varying in "correctness" and ease of use. As always, the right design depends on your needs.
You could simply create two columns in Ticket, OwnedByUserId and OwnedByGroupId, and have nullable Foreign Keys to each table....
What use is find_package() if you need to specify CMAKE_MODULE_PATH anyway?
...e. Now the software has a few dependencies. I compiled them myself and installed them on my system.
4 Answers
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Explain how finding cycle start node in cycle linked list work?
...t node in the cycle.
When the tortoise and hare meet, we have found the smallest i (the number of steps taken by the tortoise) such that Xi = X2i. Let mu represent the number of steps to get from X0 to the start of the cycle, and let lambda represent the length of the cycle. Then i = mu + alambda,...
Is it abusive to use IDisposable and “using” as a means for getting “scoped behavior” for exception
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I don't think so, necessarily. IDisposable technically is meant to be used for things that have non-managed resources, but then the using directive is just a neat way of implementing a common pattern of try .. finally { dispose }.
A purist would argue 'yes - it's abusive', ...
Named colors in matplotlib
... have been moved under the 'xkcd:' prefix since I posted this answer originally.
I really didn't change much from the matplotlib example, but here is the code for completeness.
import matplotlib.pyplot as plt
from matplotlib import colors as mcolors
colors = dict(mcolors.BASE_COLORS, **mcolors...
REST, HTTP DELETE and parameters
... natively, however most modern browsers can do these two methods via AJAX calls. See this thread for details about cross-browser support.
Update (based on additional investigation and discussions):
The scenario where the service would require the force_delete=true flag to be present violates the...
How can you use an object's property in a double-quoted string?
... @ozzy432836 You can, of course. Or use format strings. It usually doesn't really matter and comes down to personal preference.
– Joey
Jul 22 '16 at 16:19
add a c...
When should one use a spinlock instead of mutex?
...eed, because the mutex is already locked, it will go to sleep, immediately allowing another thread to run. It will continue to sleep until being woken up, which will be the case once the mutex is being unlocked by whatever thread was holding the lock before. When a thread tries to lock a spinlock an...
is vs typeof
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@nawfal, I initially thought your point about the boxing penalty made sense for struct types, but given that we're testing an object obj; variable, isn't it already boxed when this tends to be tested? Is there a case where you need to test ...
Foreign Key to non-primary key
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If you really want to create a foreign key to a non-primary key, it MUST be a column that has a unique constraint on it.
From Books Online:
A FOREIGN KEY constraint does not have to be linked only to a PRIMARY
KEY constraint in...