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SQL Server insert if not exists best practice
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Semantically you are asking "insert Competitors where doesn't already exist":
INSERT Competitors (cName)
SELECT DISTINCT Name
FROM CompResults cr
WHERE
NOT EXISTS (SELECT * FROM Competitors c
WHERE cr.Name = c.cName)
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How to reload a page using JavaScript
....pathname + window.location.search + window.location.hash;
// creates a history entry
JavaScript 1.1
window.location.replace(window.location.pathname + window.location.search + window.location.hash);
// does not create a history entry
JavaScript 1.2
window.location.reload(false);
// If we nee...
Copy a table from one database to another in Postgres
I am trying to copy an entire table from one database to another in Postgres. Any suggestions?
19 Answers
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Android check internet connection [duplicate]
I want to create an app that uses the internet and I'm trying to create a function that checks if a connection is available and if it isn't, go to an activity that has a retry button and an explanation.
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Python 3 turn range to a list
I'm trying to make a list with numbers 1-1000 in it. Obviously this would be annoying to write/read, so I'm attempting to make a list with a range in it. In Python 2 it seems that:
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How to check if a variable is set in Bash?
...t way
if [ -z ${var+x} ]; then echo "var is unset"; else echo "var is set to '$var'"; fi
where ${var+x} is a parameter expansion which evaluates to nothing if var is unset, and substitutes the string x otherwise.
Quotes Digression
Quotes can be omitted (so we can say ${var+x} instead of "${var+...
Code signing certificate for open-source projects?
I want to publish one of my applications as open-source and want to digitally sign the binaries I've created with my own certificate. (Of course, anyone else can just download the code and build it themselves with their own certificate.) I want to do this so anyone can check that this build was made...
minimize app to system tray
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C# System Tray Minimize To Tray With NotifyIcon
Minimize window to system tray
Handle the form’s Resize event. In this handler, you override the
basic functionality of the Resize event to make the form minimize to
the system tray and not ...
Is it good practice to use java.lang.String.intern()?
...eturns a canonical representation of the string, allowing interned strings to be compared using == )
20 Answers
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HTML5 Canvas Resize (Downscale) Image High Quality?
I use html5 canvas elements to resize images im my browser. It turns out that the quality is very low. I found this: Disable Interpolation when Scaling a <canvas> but it does not help to increase the quality.
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