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When to use EntityManager.find() vs EntityManager.getReference() with JPA
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I usually use getReference method when i do not need to access database state (I mean getter method). Just to change state (I mean setter method). As you should know, getReference returns a proxy object which uses a powerful featu...
JOIN queries vs multiple queries
...ase. It depends on a lot of things. Jeff Atwood (founder of this site) actually wrote about this. For the most part, though, if you have the right indexes and you properly do your JOINs it is usually going to be faster to do 1 trip than several.
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Using os.walk() to recursively traverse directories in Python
I want to navigate from the root directory to all other directories within and print the same.
13 Answers
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Correct way to use StringBuilder in SQL
... of using StringBuilder, i.e reducing memory. Is it achieved?
No, not at all. That code is not using StringBuilder correctly. (I think you've misquoted it, though; surely there aren't quotes around id2 and table?)
Note that the aim (usually) is to reduce memory churn rather than total memory used...
Skip List vs. Binary Search Tree
... Fraser and Harris's latest paper Concurrent programming without locks. Really good stuff if you're interested in lock-free data structures. The paper focuses on Transactional Memory and a theoretical operation multiword-compare-and-swap MCAS. Both of these are simulated in software as no hardwar...
Which “href” value should I use for JavaScript links, “#” or “javascript:void(0)”?
...evelopers inevitably leads to some using the return value of the function called like this:
function doSomething() {
//Some code
return false;
}
But then they forget to use return doSomething() in the onclick and just use doSomething().
A second reason for avoiding # is that the final re...
Should I use tag for icons instead of ? [closed]
...es shortness and the nice association of "i is for icon," I think it's actually the most semantic choice for an icon when a straightforward <img> tag is not practical.
1. The usage is consistent with the spec.
While it may not be what the W3 mainly had in mind, it seems to me the official sp...
Width equal to content [duplicate]
...ed elements, see this link for different techniques: http://css-tricks.com/all-about-floats/)
Demo: http://jsfiddle.net/CvJ3W/5/
Edit
If you go for the solution with display:inline-block but want to keep each item in one line, you can just add a <br> tag after each one:
<div id="contai...
Visual studio compiles fine but still shows red lines
I am using VS 2012 and it was working all fine until I started observing some funny behavior. When I open my code it shows red Underlines which we usually see when there is an error in our code. Surprisingly, code compiles all fine. I have made following observations that are not normal at all.
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Cannot generate iOS App archive in xcode
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Check Build Settings:
Skip install is NO for the main project target
Skip install is YES for framework (sub-projects) targets
In Build Phases for sub-projects, Copy Headers needs to be in Project, not Public (does not apply if building static library)
Inst...