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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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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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Why does ASP.NET webforms need the Runat=“Server” attribute?
Why do I have to specify runat="server" on all my ASP.NET controls when it is a mandatory attribute and server is the only option available in my limited knowledge of ASP.NET, and I get an error if I don't use it?
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decompiling DEX into Java sourcecode
How can one decompile Android DEX (VM bytecode) files into corresponding Java sourcecode?
17 Answers
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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...
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 ...
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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How do I create a simple 'Hello World' module in Magento?
How can the following be accomplished in Magento?
6 Answers
6
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What's the difference between passing by reference vs. passing by value?
... since fallen out of favor and is seldom used now.1
Newer languages2 tend to use a different (but similar) pair of techniques to achieve the same effects (see below) which is the primary source of confusion.
A secondary source of confusion is the fact that in "pass by reference", "reference" has a...
Why are private fields private to the type, not the instance?
In C# (and many other languages) it's perfectly legitimate to access private fields of other instances of the same type. For example:
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