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Update multiple rows in same query using PostgreSQL
...izable:
update test as t set
column_a = c.column_a
from (values
('123', 1),
('345', 2)
) as c(column_b, column_a)
where c.column_b = t.column_b;
You can add as many columns as you like:
update test as t set
column_a = c.column_a,
column_c = c.column_c
from (values
('12...
python numpy machine epsilon
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193
An easier way to get the machine epsilon for a given float type is to use np.finfo():
print(n...
How to run cron job every 2 hours
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edited Jul 14 '18 at 14:09
Mark Amery
98.9k4848 gold badges336336 silver badges379379 bronze badges
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Most efficient way of making an if-elif-elif-else statement when the else is done the most?
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100
The code...
options.get(something, doThisMostOfTheTime)()
...looks like it ought to be fast...
deleting rows in numpy array
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157
The simplest way to delete rows and columns from arrays is the numpy.delete method.
Suppose I...
Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
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119
I'd just use zip:
In [1]: from pandas import *
In [2]: def calculate(x):
...: return ...
Associativity of “in” in Python?
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123
1 in [] in 'a' is evaluated as (1 in []) and ([] in 'a').
Since the first condition (1 in []...
How to use JavaScript variables in jQuery selectors?
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edited Jun 25 '15 at 5:31
answered May 5 '11 at 2:10
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Python Dictionary to URL Parameters
... key-value pairs, and converts it into a form suitable for a URL (e.g., key1=val1&key2=val2).
If you are using Python3, use urllib.parse.urlencode()
If you want to make a URL with repetitive params such as: p=1&p=2&p=3 you have two options:
>>> import urllib
>>> a = ...