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How to force LINQ Sum() to return 0 while source collection is empty
... doesn't allow you to use "??" operator to set 0 for empty collection.
In order to avoid this situation you need to make LINQ expect "double?". You can do it by casting "(double?)l.Amount".
It doesn't affect the query to SQL but it makes LINQ working for empty collections.
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Order of member constructor and destructor calls
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In other words, are members guaranteed to be initialized by order of declaration and destroyed in reverse order?
Yes to both. See 12.6.2
6 Initialization shall proceed in the
following order:
First, and only for
the constructor of the most derived
class as described below, virtual ...
What does the ??!??! operator do in C?
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Column order manipulation using col-lg-push and col-lg-pull in Twitter Bootstrap 3
...w reading documentation on Twitter Bootstrap 3, and tried to follow column ordering as shown in this page but hit the wall. I don't understand why such a code works nor how to correctly specify the setting. What I want to show is one grid, which is consisted of length 5, and the other length 5, ...
Developing C# on Linux
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Bootstrap right Column on top on mobile view
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Use Column ordering to accomplish this.
col-md-push-6 will "push" the column to the right 6 and col-md-pull-6 will "pull" the column to the left on "md" or greater view-ports. On any smaller view-ports the columns will be in normal or...
How to cat a file containing code?
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Does order of where clauses matter in SQL?
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No, that order doesn't matter (or at least: shouldn't matter).
Any decent query optimizer will look at all the parts of the WHERE clause and figure out the most efficient way to satisfy that query.
I know the SQL Server query optimi...
ASP.NET MVC - Attaching an entity of type 'MODELNAME' failed because another entity of the same type
...ified stamp and row version on my entities, so I was getting them first in order to compare with the inbound headers. Of course, this loaded and tracked the entity that was subsequently being updated.
The fix was simply to change the repository from newing-up a context once in the constructor to ha...
Passing a std::array of unknown size to a function
...y is that its size is part of its type, so you'd have to use a template in order to implement a function that takes an std::array of arbitrary size.
gsl::span on the other hand stores its size as run-time information. This allows you to use one non-template function to accept an array of arbitrary...