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What is the difference between JOIN and UNION?
...n one table to look up column values by using the primary key in another.
Now compare the above depiction with that of a union. In a union each row within the result is from one table OR the other. In a union, columns aren’t combined to create results, rows are combined.
Both joins and union...
Does overflow:hidden applied to work on iPhone Safari?
...
Had this issue today on iOS 8 & 9 and it seems that we now need to add height: 100%;
So add
html,
body {
position: relative;
height: 100%;
overflow: hidden;
}
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im...
Serializing to JSON in jQuery [duplicate]
...ge in jQuery yesterday that utilizes the
JSON.parse method if it exists, now
that it has been completely specified.
I tend to trust what he says on JavaScript matters :)
All modern browsers (and many older ones which aren't ancient) support the JSON object natively. The current version of Cro...
How do I wrap a selection with an HTML tag in Visual Studio?
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I know this is old and you have probably found the answer by now but I would just like to add for the sake of those who might not know it that this is possible in VS 2010:
Select the code you would like to surround.
Do ctrl-k ...
Why can't Python's raw string literals end with a single backslash?
...arser enters a raw string (non Unicode one) and encounters a backslash it knows there are 2 characters (a backslash and a char following it).
This way:
r'abc\d' comprises a, b, c, \, d
r'abc\'d' comprises a, b, c, \, ', d
r'abc\'' comprises a, b, c, \, '
and:
r'abc\' comprises a...
Subtract days from a date in JavaScript
Does anybody know of an easy way of taking a date (e.g. Today) and going back X days?
32 Answers
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How can I find unused images and CSS styles in a website? [closed]
...>Audits->Remove unused CSS rules
Screenshot:
Update: 30 Jun, 2017
Now Chrome 59 provides CSS and JS code coverage. See https://developers.google.com/web/updates/2017/04/devtools-release-notes#coverage
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Should I avoid 'async void' event handlers?
I know it is considered generally a bad idea to use fire-and-forget async void methods to start tasks, because there is no track of the pending task and it is tricky to handle exceptions which might be thrown inside such a method.
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Rename a file in C#
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File.Move has an overload method now that allows you to overwrite the file - File.Move(oldPath, newPath, true)
– Ella
Apr 5 at 22:15
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How to plot two histograms together in R?
...rm(100000, 6, 2))
cukes <- data.frame(length = rnorm(50000, 7, 2.5))
# Now, combine your two dataframes into one.
# First make a new column in each that will be
# a variable to identify where they came from later.
carrots$veg <- 'carrot'
cukes$veg <- 'cuke'
# and combine into your new ...