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Does MySQL ignore null values on unique constraints?
...Result:
x
NULL
NULL
1
This is not true for all databases. SQL Server 2005 and older, for example, only allows a single NULL value in a column that has a unique constraint.
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SQL, Postgres OIDs, What are they and why are they useful?
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OIDs basically give you a built-in id for every row, contained in a system column (as opposed to...
How to reliably open a file in the same directory as a Python script
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Views vs Components in Ember.js
... intuitivepixelintuitivepixel
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What is a regular expression for a MAC Address?
...digits, separated by
hyphens - or colons :.
So:
^([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})$
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How to keep the local file or the remote file during merge using Git and the command line?
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Waiting for Dev...Waiting for Dev...
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Concatenate two string literals
... James McNellisJames McNellis
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Why is it faster to check if dictionary contains the key, rather than catch the exception in case it
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edited Apr 25 '13 at 7:13
answered Apr 19 '13 at 9:48
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Remove padding or margins from Google Charts
...ns = {'title': 'How Much Pizza I Ate Last Night',
'width': 350,
'height': 400,
'chartArea': {'width': '100%', 'height': '80%'},
'legend': {'position': 'bottom'}
};
If you want to tune it more, try changing these values or using other ...
Git submodule push
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