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How do SQL EXISTS statements work?
...M student WHERE EXISTS (SELECT 1 FROM student WHERE student.id > 1). I know what I wrote could be achieved by one simple WHERE query but I was just using it to understand EXISTS. I got all the rows. Is it indeed due to the fact that I didn't use correlated subquery? Thanks.
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Loading custom configuration files
I know I can open config files that are related to an assembly with the static ConfigurationManager.OpenExe(exePath) method but I just want to open a config that is not related to an assembly. Just a standard .NET config file.
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Latex Remove Spaces Between Items in List
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I would also like to add that the nolistsep option is now deprecated, and that its successor is nosep, which "kills all vertical spacing".
– larsac07
May 15 '16 at 18:48
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What is a singleton in C#?
...plementing the Singleton Pattern in C#" covering most of what you need to know - including some good advice regarding thread safety.
To be honest, It's very rare that you need to implement a singleton - in my opinion it should be one of those things you should be aware of, even if it's not used too...
How to frame two for loops in list comprehension python
...swering the question for readers in the future, not just the person asking now. Please edit your answer to add explanations and give an indication of what limitations and assumptions apply.
– Brian
Aug 13 at 17:25
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How to add color to Github's README.md file
...his in its GitHub integration bot's comments, for example: github.com/zeit/now/pull/2570#issuecomment-512585770
– Jacob Ford
Oct 26 '19 at 18:56
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What's the difference between an element and a node in XML?
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Now that I understand the answer...The convention is stupid. The words should be the other way around. In natural English language an 'element' is something which is the most basic building block, out of which everything else...
How do I convert a numpy array to (and display) an image?
...nting out my error. I should have created an array of shape (h,w,3). (It's now fixed, above.) The length of the first axis can be thought of as the number of rows in the array, and the length of the second axis, the number of columns. So (h, w) corresponds to an array of "height" h and "width" w. Im...
Swift compiler segmentation fault when building
...ebugger.swift. Repeat
You get a segfault in SegFaultDebugger.swift: Great! Now use binary search to pin the segfault down to a specific method until you can figure out what construct is causing it.
You get meaningful compiler errors: Great! Fix the errors. Once everything compiles, move your methods...
Using Rails serialize to save hash to database
...PDATED:
Exact implementation will depend on your database, but PostgreSQL now has json and jsonb columns which can natively store your hash/object data and allow you to query against the JSON with ActiveRecord!
change your migration and you're done.
class Migration0001
def change
add_column...