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Does MySQL ignore null values on unique constraints?
...ws multiple NULLs in a column with a unique constraint.
CREATE TABLE table1 (x INT NULL UNIQUE);
INSERT table1 VALUES (1);
INSERT table1 VALUES (1); -- Duplicate entry '1' for key 'x'
INSERT table1 VALUES (NULL);
INSERT table1 VALUES (NULL);
SELECT * FROM table1;
Result:
x
NULL
NULL
1
This i...
Maintaining the final state at end of a CSS3 animation
...applied onClick, and, using keyframes, it changes the opacity from 0 to 1 (among other things).
4 Answers
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How to convert a table to a data frame
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edited Nov 29 '16 at 20:39
Jaap
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How to determine the Boost version on a system?
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11 Answers
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Cluster analysis in R: determine the optimal number of clusters
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1024
If your question is how can I determine how many clusters are appropriate for a kmeans analys...
select and update database record with a single queryset
...et object update method:
MyModel.objects.filter(pk=some_value).update(field1='some value')
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SQL query to select dates between two dates
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21 Answers
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Twitter oAuth callbackUrl - localhost development
...bled recently. http://code.google.com/p/twitter-api/issues/detail?id=534#c1
17 Answers
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Check if my app has a new version on AppStore
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91
Here is a simple code snippet that lets you know if the current version is different
-(BOOL) ne...
Batch script: how to check for admin rights
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481
Issues
blak3r / Rushyo's solution works fine for everything except Windows 8. Running AT on Win...