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How to check if a function exists on a SQL database
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answered Mar 24 '11 at 12:30
Martin SmithMartin Smith
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How do I make a matrix from a list of vectors in R?
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KalinKalin
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add a com...
Git status - is there a way to show changes only in a specific directory?
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Sam DoidgeSam Doidge
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Add a number to each selection in Sublime Text 2, incremented once per selection
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aantonaanton
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How to handle multiple heterogeneous inputs with Logstash?
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Adam Michalik
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answered Dec 13 '13 at 8:24
Ben LimBen Lim
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How to change the foreign key referential action? (behavior)
...sers table:
mysql> SHOW CREATE TABLE UserDetails;
:
:
`User_id` int(11) DEFAULT NULL,
PRIMARY KEY (`Detail_id`),
KEY `FK_User_id` (`User_id`),
CONSTRAINT `FK_User_id` FOREIGN KEY (`User_id`) REFERENCES `Users` (`User_id`)
:
:
First step:
mysql> ALTER TABLE `UserDetails` DROP FOR...
Efficient way to apply multiple filters to pandas DataFrame or Series
...numpy) allow for boolean indexing, which will be much more efficient:
In [11]: df.loc[df['col1'] >= 1, 'col1']
Out[11]:
1 1
2 2
Name: col1
In [12]: df[df['col1'] >= 1]
Out[12]:
col1 col2
1 1 11
2 2 12
In [13]: df[(df['col1'] >= 1) & (df['col1'] <=1 )]
Out...
How can I check whether a numpy array is empty or not?
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Colonel PanicColonel Panic
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Are empty HTML5 data attributes valid?
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Community♦
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answered May 20 '14 at 6:14
useruser
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How to get last items of a list in Python?
... python CLI interpreter:
>>> a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]
>>> a
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]
>>> a[-9:]
[4, 5, 6, 7, 8, 9, 10, 11, 12]
the important line is a[-9:]
shar...