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NULL values inside NOT IN clause
... not in constraint had one null value (bad data) which caused that query to return a count of 0 records. I sort of understand why but I could use some help fully grasping the concept.
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How can I add to List
... Double extends Number
So, given this, what type of object could you add to List foo3 that would be legal after any of the above possible ArrayList assignments:
You can't add an Integer because foo3 could be pointing at a List<Double>.
You can't add a Double because foo3 could be pointing ...
What is the copy-and-swap idiom?
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Any class that manages a resource (a wrapper, like a smart pointer) needs to implement The Big Three. While the goals and implementation of the copy-constructor and destructor are straightforward, the copy-assignment operator is arguably the most nuanced and difficult. How should it be done? What p...
What is the difference between user and kernel modes in operating systems?
... In Kernel mode, the executing code has complete and unrestricted
access to the underlying hardware. It
can execute any CPU instruction and
reference any memory address. Kernel
mode is generally reserved for the
lowest-level, most trusted functions
of the operating system. Crashes in
k...
Creating an API for mobile applications - Authentication and Authorization
I'm looking to create a (REST) API for my application. The initial/primary purpose will be for consumption by mobile apps (iPhone, Android, Symbian, etc). I've been looking into different mechanisms for authentication and authorization for web-based APIs (by studying other implementations). I've ...
Sample settings.xml for maven
How to configure settings.xml in Maven? Also, please share a sample settings.xml .
3 Answers
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Delete multiple records using REST
...DELETE the (single) resource at /records/1;2;3” — So a 2xx response to this may cause them to purge their cache of /records/1;2;3; not purge /records/1, /records/2 or /records/3; proxy a 410 response for /records/1;2;3, or other things that don't make sense from your point of view.
This choice ...
Why should I avoid using Properties in C#?
..., Jeffrey Richter said that he doesn't like properties, and recommends not to use them. He gave some reason, but I don't really understand. Can anyone explain to me why I should or should not use properties?
In C# 3.0, with automatic properties, does this change?
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RESTfully design /login or /register resources?
I was designing a web app and then stopped to think about how my api should be designed as a RESTful web service. For now, most of my URI's are generic and might apply to various web apps:
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What are the differences between NP, NP-Complete and NP-Hard?
...itive definitions, since the technical definitions require quite some time to understand. First of all, let's remember a preliminary needed concept to understand those definitions.
Decision problem: A problem with a yes or no answer.
Now, let us define those complexity classes.
P
P is a comp...