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What is Persistence Context?
I am new to the Java world and JPA. I was studying JPA and came across many new terms like Entity, persistence. While reading, I could not understand the exact definition for Persistence Context .
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Are braces necessary in one-line statements in JavaScript?
I once heard that leaving the curly braces in one-line statements could be harmful in JavaScript. I don't remember the reasoning anymore and a Google search did not help much.
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Why use pointers? [closed]
I know this is a really basic question, but I've just started with some basic C++ programming after coding a few projects with high-level languages.
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How are parameters sent in an HTTP POST request?
In an HTTP GET request, parameters are sent as a query string :
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What is meant by 'first class object'?
In a recent question , I received suggestions to talk on, amongst other things, the aspect of JavaScript where functions are 'first class' objects. What does the 'first class' mean in this context, as opposed to other objects?
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What is the difference between a symbolic link and a hard link?
Recently I was asked this during a job interview. I was honest and said I knew how a symbolic link behaves and how to create one, but do not understand the use of a hard link and how it differs from a symbolic one.
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What is so bad about singletons? [closed]
The singleton pattern is a fully paid up member of the GoF 's patterns book , but it lately seems rather orphaned by the developer world. I still use quite a lot of singletons, especially for factory classes , and while you have to be a bit careful about multithreading issues (like any class ac...
On Duplicate Key Update same as insert
I've searched around but didn't find if it's possible.
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Python data structure sort list alphabetically
I am a bit confused regarding data structure in python; () , [] , and {} . I am trying to sort a simple list, probably since I cannot identify the type of data I am failing to sort it.
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Unnecessary curly braces in C++?
When doing a code review for a colleague today I saw a peculiar thing. He had surrounded his new code with curly braces like this:
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