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Unique constraint that allows empty values in MySQL
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Yes, you can do this. See the MySQL reference (version 5.5).
A UNIQUE index creates a constraint such that all values in the index must be distinct. An error occurs if you try to add a new row with a key value that matches an existing row. For all engines, a UNIQUE index all...
Django - Difference between import django.conf.settings and import settings
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135
import settings
Will import settings(.py) module of your Django project (if you are writing th...
What is the best way to clear a session variable in rails?
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SigurdSigurd
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How to do a less than or equal to filter in Django queryset?
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Less than or equal:
User.objects.filter(userprofile__level__lte=0)
Greater than or equal:
U...
How to get Top 5 records in SqLite?
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SELECT * FROM Table_Name LIMIT 5;
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How can I make git show a list of the files that are being tracked?
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If you want to list all the files currently being tracked under the branch master, you could use...
Is SecureRandom thread safe?
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ericksonerickson
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Referencing another schema in Mongoose
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5
What is the "ref" field for? I can't find documentation on it.
– basickarl
Jun 30 '16 at 17:58
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Restart/undo conflict resolution in a single file
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Found the solution here: http://gitster.livejournal.com/43665.html
git checkout -m FILE
This restores the unresolved state, including all information about parent and merge base, which allows restarting the resolution.
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Why does “while(true)” without “Thread.sleep” cause 100% CPU usage on Linux but not on Windows?
... 100% and 4 cores are 400%.
With IRIX mode off, 1 fully utilized core is 25% and 4 cores are 100%.
This means that by default, top on Linux will show an infinite loop as ~100% and Windows will show it as ~25%, and it means exactly the same thing.
You can toggle IRIX mode while top is running wi...