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What are '$$' used for in PL/pgSQL
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The dollar signs are used for dollar quoting and are in no way specific to function definitions. It can be used to replace single quotes practically anywhere in SQL scripts.
The body of a function happens to be a string literal which has to be enclosed in single quote...
NumPy or Pandas: Keeping array type as integer while having a NaN value
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This capability has been added to pandas (beginning with version 0.24):
https://pandas.pydata.org/pandas-docs/version/0.24/whatsnew/v0.24.0.html#optional-integer-na-support
At this point, it requires the use of extension dtype Int64 (capitalized), rather than...
What is sys.maxint in Python 3?
I've been trying to find out how to represent a maximum integer, and I've read to use "sys.maxint" . However, in Python 3 when I call it I get:
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Load different colorscheme when using vimdiff
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If you're calling vimdiff from the command-line, put the following in your .vimrc:
if &diff
colorscheme some_other_scheme
endif
If you're using vimdiff from within vim, you'd either have to override the commands you use to start/stop it (e.g. diffthis, ...
What is the point of Lookup?
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It's a cross between an IGrouping and a dictionary. It lets you group items together by a key, but then access them via that key in an efficient manner (rather than just iterating over them all, which is what GroupBy lets you do).
For example, you could take...
Update a local branch with the changes from a tracked remote branch
...nch
(see:
"How do you make an existing git branch track a remote branch?" and
"Git: Why do I need to do --set-upstream-to all the time?"
)
git branch -f --track my_local_branch origin/my_remote_branch
# OR (if my_local_branch is currently checked out):
$ git branch --set-upstream-to my_local_bran...
Can someone explain the HTML5 aria-* attribute?
...know what the aria-* attributes are used for. What values can they have, and are they defined values or can I create my own values?
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Convert list to array in Java [duplicate]
...trinsified, making the performance of the empty array version
the same and sometimes even better, compared to the pre-sized
version. Also passing pre-sized array is dangerous for a concurrent or
synchronized collection as a data race is possible between the
size and toArray call which ...
How to get all of the immediate subdirectories in Python
... return the full path to all current subdirectories.
tl;dr:
Always use scandir:
list_subfolders_with_paths = [f.path for f in os.scandir(path) if f.is_dir()]
Bonus: With scandir you can also simply only get folder names by using f.name instead of f.path.
This (as well as all other functions b...
Why is $$ returning the same id as the parent process?
I have problem with Bash, and I don't know why.
Under shell, I enter:
6 Answers
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