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How do I automatically update a timestamp in PostgreSQL
I want the code to be able to automatically update the time stamp when a new row is inserted as I can do in MySQL using CURRENT_TIMESTAMP.
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How to do error logging in CodeIgniter (PHP)
... wouldn't be publicly accessible- but you'll never know. Make sure to have all of this precautions in place if you change the default application/logs directory.
– Vincent Edward Gedaria Binua
Jan 29 '15 at 2:56
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Principal component analysis in Python
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Months later, here's a small class PCA, and a picture:
#!/usr/bin/env python
""" a small class for Principal Component Analysis
Usage:
p = PCA( A, fraction=0.90 )
In:
A: an array of e.g. 1000 observations x 20 variables, 1000 rows x 20 colum...
Using switch statement with a range of value in each case?
... great and is simple. Also if you want to select numbers not in the range all you need is if(!isBetween... , good job.
– a54studio
Jul 20 '13 at 13:43
1
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Constantly print Subprocess output while process is running
... return_code = popen.wait()
if return_code:
raise subprocess.CalledProcessError(return_code, cmd)
# Example
for path in execute(["locate", "a"]):
print(path, end="")
share
|
impro...
Fastest way to get the first object from a queryset in django?
...eturn None if there aren't any. There are lots of ways to do this which all work. But I'm wondering which is the most performant.
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How should one use std::optional?
...std::string s, int& i);
Another way that this could be done is especially bad:
int* try_parse_int(std::string s); //return nullptr if fail
This requires dynamic memory allocation, worrying about ownership, etc. - always prefer one of the other two signatures above.
Another example:
clas...
What Does 'Then' Really Mean in CasperJS
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then() basically adds a new navigation step in a stack. A step is a javascript function which can do two different things:
waiting for the previous step - if any - being executed
waiting for a requested url and related page to load
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Determining Referer in PHP
...s the most reliable and secure way to determine what page either sent, or called (via AJAX), the current page. I don't want to use the $_SERVER['HTTP_REFERER'] , because of the (lack of) reliability, and I need the page being called to only come from requests originating on my site.
Edit: I am...
One-liner to check whether an iterator yields at least one element?
... Similarly if you need to check if the iterator is empty, one could use all(False for _ in iterator) will check if the iterator is empty. (all returns True if the iterator is empty, otherwise it stops when it sees the first False element)
– KGardevoir
Apr 3 ...