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When is del useful in python?
I can't really think of any reason why python needs the del keyword (and most languages seem to not have a similar keyword). For instance, rather than deleting a variable, one could just assign None to it. And when deleting from a dictionary, a del method could be added.
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jQuery get specific option tag text
All right, say I have this:
21 Answers
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How do I check if a column is empty or null in MySQL?
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This will select all rows where some_col is NULL or '' (empty string)
SELECT * FROM table WHERE some_col IS NULL OR some_col = '';
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Growing Amazon EBS Volume sizes [closed]
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All great recommendations, and I thought I'd add this article I found, which relates to expanding a Windows Amazon EC2 EBS instance using the Amazon Web UI tools to perform the necessary changes. If you're not comfortable usi...
Non-static variable cannot be referenced from a static context
... what you see with the class "car". The class contains which is similar to all cars. Think of it as a template or an idea.
At the same time, the car you see is an instance of the class "car" since it has all the properties which you expect: There is someone driving it, it has an engine, wheels.
So...
What causes java.lang.IncompatibleClassChangeError?
...out recompiling the client code. Java Language Specification §13 details all such changes, most prominently, changing non-static non-private fields/methods to be static or vice versa.
Recompile the client code against the new library, and you should be good to go.
UPDATE: If you publish a public...
Get the Row(s) which have the max count in groups using groupby
How do I find all rows in a pandas dataframe which have the max value for count column, after grouping by ['Sp','Mt'] columns?
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How to check if a String contains only ASCII?
The call Character.isLetter(c) returns true if the character is a letter. But is there a way to quickly find if a String only contains the base characters of ASCII?
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Getting Git to work with a proxy server - fails with “Request timed out”
...thout proxy:
Command to use:
git config --global --unset http.proxy
Finally, to check the currently set proxy:
git config --global --get http.proxy
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How to clean project cache in Intellij idea like Eclipse's clean?
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Depending on the version you are running. It is basically the same just go to
File -> Invalidate caches, then restart Intellij
or
File -> Invalidate caches / Restart
The main difference is that in older versions you had to manually restart as cache files are not removed...