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Best way to store time (hh:mm) in a database
...times in a database table but only need to store the hours and minutes.
I know I could just use DATETIME and ignore the other components of the date, but what's the best way to do this without storing more info than I actually need?
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Is storing a delimited list in a database column really that bad?
...ne type of query at the expense of other uses of the data, so be sure you know which of your queries need to be treated so specially that they deserve denormalization.
* MySQL 8.0 no longer supports this word-boundary expression syntax.
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Splitting templated C++ classes into .hpp/.cpp files--is it possible?
...and lib files to hide the implementation, it is simply not possible.
To know why, let us look at the compilation process. The header files are never compiled. They are only preprocessed. The preprocessed code is then clubbed with the cpp file which is actually compiled. Now if the compiler has to ...
Can a foreign key be NULL and/or duplicate?
...inition. Null by definition is not a value. Null means that we do not yet know what the value is.
Let me give you a real life example. Suppose you have a database that stores sales proposals. Suppose further that each proposal only has one sales person assigned and one client. So your proposal tab...
How can I rollback a github repository to a specific commit?
My github has 100 commits in it right now. I need to rollback the repository to commit 80, and remove all the subsequent ones.
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Difference between numpy.array shape (R, 1) and (R,)
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1. The meaning of shapes in NumPy
You write, "I know literally it's list of numbers and list of lists where all list contains only a number" but that's a bit of an unhelpful way to think about it.
The best way to think about NumPy arrays is that they consist of two parts, ...
Standardize data columns in R
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EDIT 3 (2020): Thanks to @mj_whales: the old solution is deprecated and now we need to use mutate_at.
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How can I change IIS Express port for a site
...icking the Create Virtual Directory button. Doing that made the different; now it works. But why is that necessary?
– Rod
Jun 1 '18 at 17:20
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jQuery append() - return appended elements
...et) (note the "To" bit) to add that it to the end of #mydiv.
Because you now start with $(newHtml) the end result of appendTo('#myDiv') is that new bit of html, and the .effects(...) call will be on that new bit of html too.
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HTML 5: Is it , , or ?
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@Marco: Huh, I didn't know document.write doesn't work in xhtml -- thanks for sharing. I agree that it'd be silly for webapps to try and do anything without Javascript, but I was trying to say that websites that rely almost 100% percent on Javascr...