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What does SQL clause “GROUP BY 1” mean?
Someone sent me a SQL query where the GROUP BY clause consisted of the statement: GROUP BY 1 .
6 Answers
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Persistent invalid graphics state error when using ggplot2
I believe my dataframe is okay and my code is okay. In fact, I have eliminated parts of the dataframe and most of the graphing code to make things as basic as possible. But still, I get:
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How do I break out of a loop in Perl?
I'm trying to use a break statement in a for loop, but since I'm also using strict subs in my Perl code, I'm getting an error saying:
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How do I create a datetime in Python from milliseconds?
I can create a similar Date object in Java by java.util.Date(milliseconds) . How do I create the comparable in Python?
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How should I copy Strings in Java?
At this point, the backup variable still contains the original value "hello" (this is because of String's immutability right?).
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Suppress/ print without b' prefix for bytes in Python 3
Just posting this so I can search for it later, as it always seems to stump me:
4 Answers
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Check if key exists and iterate the JSON array using Python
I have a bunch of JSON data from Facebook posts like the one below:
7 Answers
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Purpose of asterisk before a CSS property
The following is taken from the Yahoo CSS reset. Can someone please explain the purpose of the asterisks?
6 Answers
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git push to specific branch
Even after reading this question: git-push-current-branch , I am still having difficulty figuring out how I should write my git push command. As mentioned in the question link, it's not clear from the documentation.
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How to get the PATH environment-variable separator in Python?
When multiple directories need to be concatenated, as in an executable search path, there is an os-dependent separator character. For Windows it's ';' , for Linux it's ':' . Is there a way in Python to get which character to split on?
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