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Difference between
...from type C2.
Notes
Here the complete hierarchy if you wish to make some tests
interface A1{}
interface A2{}
interface A3{}
interface A4{}
interface B1 extends A1{}
interface B2 extends A1,A2{}
interface B3 extends A3,A4{}
interface B4 extends A4{}
interface C1 extends B2{}
interface C2 extends...
Is multiplication and division using shift operators in C actually faster?
... clearly (i.e. i*2 rather than i << 1) and let it decide what the fastest assembly/machine code sequence is. It's even possible that the processor itself has implemented the multiply instruction as a sequence of shifts & adds in microcode.
Bottom line--don't spend a lot of time worrying ...
How can I add reflection to a C++ application?
...ot supported by C++ out of the box. This is sad because it makes defensive testing a pain.
There are several approaches to doing reflection:
use the debug information (non portable).
Sprinkle your code with macro's/templates or some other source approach (looks ugly)
Modify a compiler such as clang...
What is the dependency inversion principle and why is it important?
...object will be indpendent of the implementation of the other objects. Unit testing is now simple. Later refactoring for reuse is possible. Design changes have very limited change scopes. Design problems don not cascade. See also the AI pattern "Blackboard" for data dependaecy inversion. Together, ve...
Maintain the aspect ratio of a div with CSS
...e a 3px by 2px image. It may work under some circumstances, but I haven't tested it, and it would probably be a good idea to avoid.
You should probably already have a minimum width like this defined for fluid elements of your web site. If not, it is a good idea to do so in order to avoid choppi...
Real life example, when to use OUTER / CROSS APPLY in SQL
...--------x-------x
This will bring wrong results ie, it will bring only latest two dates data from Details table irrespective of Id even though we join with Id. So the proper solution is using OUTER APPLY.
SELECT M.ID,M.NAME,D.PERIOD,D.QTY
FROM MASTER M
OUTER APPLY
(
SELECT TOP 2 ID, PERIOD,QT...
What do Clustered and Non clustered index actually mean?
... @MartinSmith I have reproduced and confirmed the results of your test on SQL Server 2014. I get 95% fragmentation of the index after the initial insert. After index rebuild the fragmentation was 0% and the values were ordered. I am wondering, can we say that The only time the data rows in ...
Why C# fails to compare two object types with each other but VB doesn't?
...’s what VB does:
In VB with Option Strict On, a comparison via = always tests for value equality and never for reference equality. In fact, your code doesn’t even compile once you switch Option Strict On because System.Object doesn’t define an Operator=. You should always have this option on,...
ASP.NET Identity's default Password Hasher - How does it work and is it secure?
...icrosoft.com/en-us/library/yx129kfs(v=vs.110).aspx
The stored hash and the test hash are then compared.
The Hash
Under the covers the hash is generated using the SHA1 hash function (https://en.wikipedia.org/wiki/SHA-1).
This function is iteratively called 1000 times (In the default Identity imp...
Update relationships when saving changes of EF4 POCO objects
...calar preperties (= not navigation properties and relations). I rather not test this methods with complex types nested in entity.
Other proposed solution
Instead of real Merge functionality EF team provides something called Self Tracking Entities (STE) which don't solve the problem. First of all ...