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Find which commit is currently checked out in Git
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You have at least 5 different ways to view the commit you currently have checked out into your working copy during a git bisect session (note that options 1-4 will also work when you're not doing a bisect):
git show.
git log -1.
Bash prompt.
gi...
How can I increment a char?
...o the above works (ord receives Unicode chars and chr produces them).
But if you're interested in bytes (such as for processing some binary data stream), things are even simpler:
>>> bstr = bytes('abc', 'utf-8')
>>> bstr
b'abc'
>>> bstr[0]
97
>>> bytes([97, 98, ...
How to access environment variable values?
...mes you might need to see a complete list!
# using get will return `None` if a key is not present rather than raise a `KeyError`
print(os.environ.get('KEY_THAT_MIGHT_EXIST'))
# os.getenv is equivalent, and can also give a default value instead of `None`
print(os.getenv('KEY_THAT_MIGHT_EXIST', defa...
How to access component methods from “outside” in ReactJS?
...t;
</div>
);
}
}
Note: This will only work if the child component is declared as a class, as per documentation found here: https://facebook.github.io/react/docs/refs-and-the-dom.html#adding-a-ref-to-a-class-component
Update 2019-04-01: Changed example to use a class ...
Difference between Python datetime vs time modules
I am trying to figure out the differences between the datetime and time modules, and what each should be used for.
4 An...
Using ls to list directories and their total sizes
...dable *
Explanation:
du: Disk Usage
-s: Display a summary for each specified file. (Equivalent to -d 0)
-h: "Human-readable" output. Use unit suffixes: Byte, Kibibyte (KiB), Mebibyte (MiB), Gibibyte (GiB), Tebibyte (TiB) and Pebibyte (PiB). (BASE2)
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Make: how to continue after a command fails?
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For example,
clean:
-rm -f *.o
This causes rm to continue even if it is unable to remove a file.
All examples are with rm, but are applicable to any other command you need to ignore errors from (i.e. mkdir).
sh...
How to output messages to the Eclipse console when developing for Android
...e reference for Log.
The benefits of using LogCat are that you can print different colours depending on your log type, e.g.: Log.d prints blue, Log.e prints orange. Also you can filter by log tag, log message, process id and/or by application name. This is really useful when you just want to see yo...
Can I restore a single table from a full mysql mysqldump file?
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True. I was not sure if the table names in all mysql dumps are always surrounded by backquote or if "CREATE TABLE mytable" could also be possible. We can easily adapt the first regexp if we know how the dump looks like. A second problem could be...
Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign
...and the dataset
Try running your query natively and look at the results, if the resultset is not too large. If you've eliminated null values, then my guess is that the primary key columns is being duplicated.
Or, to see the exact error, you can manually add a Try/Catch block to the generated code...