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MySQL: multiple tables or one table with many columns?
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Any time information is one-to-one (each user has one name and password), then it's probably better to have it one table, since it reduces the number of joins the database will need to do to retrieve results. I think some databases have a limit on the number of columns per table, but...
What exactly are unmanaged resources?
...g Dispose on that object, or (in C#) using the using statement which will handle calling Dispose for you.
If you neglect to Dispose of your unmanaged resources correctly, the garbage collector will eventually handle it for you when the object containing that resource is garbage collected (this is "...
Can the Android layout folder contain subfolders?
...ng every XML layout file inside the 'res/layout' folder, so it is feasible and simple to manage small projects, but when there is a case of large and heavy projects, then there should be a hierarchy and sub-folders needed inside the layout folder.
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Delete all local changesets and revert to tree
I'm using Mercurial and I've got into a terrible mess locally, with three heads. I can't push, and I just want to delete all my local changes and commits and start again with totally clean code and a clean history.
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How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
...o do an upsert, which is what MySQL calls INSERT ... ON DUPLICATE UPDATE and the standard supports as part of the MERGE operation.
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lenses, fclabels, data-accessor - which library for structure access and mutation is better
There are at least three popular libraries for accessing and manipulating fields of records. The ones I know of are: data-accessor, fclabels and lenses.
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Checking if a double (or float) is NaN in C++
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According to the IEEE standard, NaN values have the odd property that comparisons involving them are always false. That is, for a float f, f != f will be true only if f is NaN.
Note that, as some comments below have pointed out, not all compilers ...
Why does Unicorn need to be deployed together with Nginx?
I would like to know the difference between Nginx and Unicorn. As far as I understand, Nginx is a web server while Unicorn is a Ruby HTTP server.
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ReactJS state vs prop
This may be treading that line between answerable and opinionated, but I'm going back and forth as to how to structure a ReactJS component as complexity grows and could use some direction.
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What is trunk, branch and tag in Subversion? [duplicate]
What is a trunk, branch and tag in Subversion and what are the best practices to use them?
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