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Get records with max value for each group of grouped SQL results
..., age desc, Person) x
group by `Group`
This works because in mysql you're allowed to not aggregate non-group-by columns, in which case mysql just returns the first row. The solution is to first order the data such that for each group the row you want is first, then group by the columns you want the...
How to create a .gitignore file
.... However, I can't find it in my project folder. Isn't it created automatically by Xcode? If not, what command allows me to create one?
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How to determine the number of days in a month in SQL Server?
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All of the solutions mentioned here pale in comparison to the elegance of @Mikael Eriksson's answer. That works whenever a valid date is provided without crazy workarounds for niche cases and is far simpler code - I'd highly...
Rails migration: t.references with alternative name?
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You can do this all in the initial migration/column definition (at least currently in Rails 5):
t.references :transferable_as, index: true, foreign_key: {to_table: :courses}
t.references :same_as, index: true, foreign_key: {to_table: :cours...
How do you cast a List of supertypes to a List of subtypes?
...However, you can cast through an intermediate wildcard type and it will be allowed (since you can cast to and from wildcard types, just with an unchecked warning):
List<TestB> variable = (List<TestB>)(List<?>) collectionOfListA;
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How to avoid long nesting of asynchronous functions in Node.js
... I'm just a newbie in Node.js, so as far as I understand, if I want to use all of them in a single page (HTTP response) I'd have to nest them all:
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How to uncheck checkbox using jQuery Uniform library
...oken. Here's an updated fiddle. If you mean that it'll have issues specifically in 1.6, then that's probably true since jQuery changed then reverted behavior of .attr(). Using 1.6 or higher, you should really be using .prop().
– user113716
Aug 25 '11 at 16:42
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How to create a sub array from another array in Java?
...ave taken me a long while before I figured it out myself. Eclipse automatically imported org.bouncycastle.util.Arrays.
– anddero
Jul 19 '17 at 12:30
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Link and execute external JavaScript file hosted on GitHub
...GitHub’s official solution to this problem.
raw.githubusercontent makes all files use the text/plain MIME type, even if the file is a CSS or JavaScript file. So going to https://raw.githubusercontent.com/‹user›/‹repo›/‹branch›/‹filepath› will not be the correct MIME type but inste...
When do you use POST and when do you use GET?
... POST action in the address bar of your browser. Use GET when it's safe to allow a person to call an action. So a URL like:
http://myblog.org/admin/posts/delete/357
Should bring you to a confirmation page, rather than simply deleting the item. It's far easier to avoid accidents this way.
POST is...