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Can enums be subclassed to add new elements?
I want to take an existing enum and add more elements to it as follows:
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Difference between JOIN and INNER JOIN
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They are functionally equivalent, but INNER JOIN can be a bit clearer to read, especially if the query has other join types (i.e. LEFT or RIGHT or CROSS) included in it.
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Is it possible to GROUP BY multiple columns using MySQL?
Is it possible to GROUP BY more than one column in a MySQL SELECT query? For example:
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How to find the largest file in a directory and its subdirectories?
...forming various commands on a directory that has a number of folders under it as well.
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Read file data without saving it in Flask
I am writing my first flask application. I am dealing with file uploads, and basically what I want is to read the data/content of the uploaded file without saving it and then print it on the resulting page. Yes, I am assuming that the user uploads a text file always.
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PreparedStatement IN clause alternatives?
What are the best workarounds for using a SQL IN clause with instances of java.sql.PreparedStatement , which is not supported for multiple values due to SQL injection attack security issues: One ? placeholder represents one value, rather than a list of values.
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Which comment style should I use in batch files?
I've been writing some batch files, and I ran into this user guide , which has been quite informative. One thing it showed me was that lines can be commented not just with REM , but also with :: . It says:
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What are the differences between “=” and “
...ons in a braced list of expressions.
Let’s not put too fine a point on it: the R documentation is (subtly) wrong [1]. This is easy to show: we just need to find a counter-example of the = operator that isn’t (a) at the top level, nor (b) a subexpression in a braced list of expressions (i.e. {...
Match whitespace but not newlines
I sometimes want to match whitespace but not newline.
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How to “log in” to a website using Python's Requests module?
I am trying to post a request to log in to a website using the Requests module in Python but its not really working. I'm new to this...so I can't figure out if I should make my Username and Password cookies or some type of HTTP authorization thing I found (??).
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