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Create unique constraint with null columns
...or may not be useful. In extreme situations it might even help to maintain all three indexes (the two partial ones and a total on top).
Aside: I advise not to use mixed case identifiers in PostgreSQL.
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get list from pandas dataframe column
...rame columns are Pandas Series when you pull them out, which you can then call x.tolist() on to turn them into a Python list. Alternatively you cast it with list(x).
import pandas as pd
data_dict = {'one': pd.Series([1, 2, 3], index=['a', 'b', 'c']),
'two': pd.Series([1, 2, 3, 4], inde...
What is the difference between attribute and property? [closed]
...roperties.
To further confuse things, changes to the properties will typically update the attributes.
For example, changing the element.href property will update the href attribute on the element, and that'll be reflected in a call to element.getAttribute('href').
However if you subsequently read...
Read file data without saving it in Flask
...iting 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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Embedding DLLs in a compiled executable
...to embed resources in your assembly. It's available as NuGet package.
Install-Package Costura.Fody
After adding it to the project, it will automatically embed all references that are copied to the output directory into your main assembly. You might want to clean the embedded files by adding a tar...
How can I use xargs to copy files that have spaces and quotes in their names?
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You can combine all of that into a single find command:
find . -iname "*foobar*" -exec cp -- "{}" ~/foo/bar \;
This will handle filenames and directories with spaces in them. You can use -name to get case-sensitive results.
Note: The ...
How to permanently set $PATH on Linux/Unix? [closed]
...t. The actual solution depends on the purpose.
The variable values are usually stored in either a list of assignments or a shell script that is run at the start of the system or user session. In case of the shell script you must use a specific shell syntax and export or set commands.
System wide
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How to find where gem files are installed
I can finds gems that are installed using gem list , but it doesn't show me where the gems are installed.
10 Answers
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How to quickly check if folder is empty (.NET)?
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There is a new feature in Directory and DirectoryInfo in .NET 4 that allows them to return an IEnumerable instead of an array, and start returning results before reading all the directory contents.
What's New in the BCL in .NET 4 Beta 1
Directory.EnumerateFileSystemEntries method overloads
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Can I replace groups in Java regex?
I have this code, and I want to know, if I can replace only groups (not all pattern) in Java regex.
Code:
7 Answers
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