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How can I pass a member function where a free function is expected?
...unction static in which case it doesn't require any object to be called on and you can use it with the type void (*)(int, int).
If you need to access any non-static member of your class and you need to stick with function pointers, e.g., because the function is part of a C interface, your best opt...
What are the main performance differences between varchar and nvarchar SQL Server data types?
... most applications. However, if you need to support double-byte languages and you only have single-byte support in your database schema it's really expensive to go back and modify throughout your application.
The cost of migrating one application from varchar to nvarchar will be much more than t...
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.
You could create M:M referen...
Using switch statement with a range of value in each case?
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This works great and is simple. Also if you want to select numbers not in the range all you need is if(!isBetween... , good job.
– a54studio
Jul 20 '13 at 13:43
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How does @synchronized lock/unlock in Objective-C?
Does @synchronized not use "lock" and "unlock" to achieve mutual exclusion? How does it do lock/unlock then?
5 Answers
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How do I interpret precision and scale of a number in a database?
...rget that if you're using a system that allows you to pre-define precision and scale of an input for a percentage in something like Microsoft Access, you must consider the percent as it's whole number form. In this case, 25.5% would require precision 4 and scale of 3 (not one) since we have to cons...
Pythonic way to print list items
...List not working, you can just use the following which does the same thing and is still one line:
for p in myList: print p
For a solution that uses '\n'.join(), I prefer list comprehensions and generators over map() so I would probably use the following:
print '\n'.join(str(p) for p in myList)
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How to get a random number between a float range?
randrange(start, stop) only takes integer arguments. So how would I get a random number between two float values?
4 Answer...
What encoding/code page is cmd.exe using?
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Yes, it’s frustrating—sometimes type and other programs
print gibberish, and sometimes they do not.
First of all, Unicode characters will only display if the
current console font contains the characters. So use
a TrueType font like Lucida Console instead of the...
LINQ with groupby and count
...g>, where each Grouping itself exposes the Key used to create the group and also is an IEnumerable<T> of whatever items are in your original data set. You just have to call Count() on that Grouping to get the subtotal.
foreach(var line in data.GroupBy(info => info.metric)
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