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Is it possible to Pivot data using LINQ?
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GroupBy in Linq does not work the same as SQL. In SQL, you get the key and aggregates (row/column shape). In Linq, you get the key and any elements as children of the key (hierarchical shape). To pivot, you must project the hierarchy back into a row/column form of your choosing.
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How do I reverse a C++ vector?
...ed Jan 16 '12 at 8:46
Ivaylo StrandjevIvaylo Strandjev
62.1k1313 gold badges104104 silver badges159159 bronze badges
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Does const mean thread-safe in C++11?
...ad-safe in C++11. Is that true?
It is somewhat true...
This is what the Standard Language has to say on thread-safety:
[1.10/4]
Two expression evaluations conflict if one of them modifies a memory location (1.7) and the other one accesses or modifies the same memory location.
[1.10/21]
The executi...
Indexes of all occurrences of character in a string
...e final result, this seems to output -1 at the end an I don't quite understand why! thanks!!
– Trufa
Feb 17 '11 at 20:55
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Get current time in milliseconds in Python?
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IMO I'd use floor and not round, but that's just me. If someone asks what the hour is, and it's 7:32, the number they probably want is 7, not 8.
– davr
Sep 9 '13 at 20:37
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How can I use interface as a C# generic type constraint?
... constraints to allow, were focused on ones that would let generic classes and methods do things with generic types that they otherwise could not, rather than on preventing them from being used in nonsensical ways. That having been said, an interface constraint on T should allow reference compariso...
What is the difference between 'typedef' and 'using' in C++11?
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All standard references below refers to N4659: March 2017 post-Kona working draft/C++17 DIS.
Typedef declarations can, whereas alias declarations cannot, be used as initialization statements
But, with the first two non-template e...
C# 4.0 optional out/ref arguments
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As already mentioned, this is simply not allowed and I think it makes a very good sense.
However, to add some more details, here is a quote from the C# 4.0 Specification, section 21.1:
Formal parameters of constructors, methods, indexers and delegate types can be declar...
Generate class from database table
... end ColumnType,
case
when col.is_nullable = 1 and typ.name in ('bigint', 'bit', 'date', 'datetime', 'datetime2', 'datetimeoffset', 'decimal', 'float', 'int', 'money', 'numeric', 'real', 'smalldatetime', 'smallint', 'smallmoney', 'time', 'tinyint', 'uniqueidentifier')
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How to pass data from 2nd activity to 1st activity when pressed back? - android
I've 2 activities, Activity1 and Activity2 .
9 Answers
9
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