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Can you create nested WITH clauses for Common Table Expressions?
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Essentially the post means, that you can't do it, but it is not a big problem.
– peterh - Reinstate Monica
May 30 '17 at 14:40
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Rails 3 execute custom sql query without a model
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Maybe try this:
ActiveRecord::Base.establish_connection(...)
ActiveRecord::Base.connection.execute(...)
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How to check if a table exists in a given schema
... (like OIDs) gets lost in translation from the system catalogs - which actually carry all information.
System catalogs
Your question was:
How to check whether a table exists?
SELECT EXISTS (
SELECT FROM pg_catalog.pg_class c
JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHE...
Calculate the median of a billion numbers
...bably too late if this had been an interview, but never mind:
Machine 1 shall be called the "control machine", and for the sake of argument either it starts with all the data, and sends it in equal parcels to the other 99 machines, or else the data starts evenly distributed between the machines, an...
Is it safe to use -1 to set all bits to true?
...s one:
unsigned long a = ~0u;
It won't necessarily store a pattern with all bits 1 into a. But it will first create a pattern with all bits 1 in an unsigned int, and then assign it to a. What happens when unsigned long has more bits is that not all of those are 1.
And consider this one, which wi...
How to get existing fragments when using FragmentPagerAdapter
...agerAdapter , as a helper class that implements the management of tabs and all details of connecting a ViewPager with associated TabHost . I have implemented FragmentPagerAdapter just as same as it is provided by the Android sample project Support4Demos .
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Generate random numbers with a given (numerical) distribution
...> choices(population, weights)
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The optional keyword-only argument k allows one to request more than one sample at once. This is valuable because there's some preparatory work that random.choices has to do every time it's called, prior to generating any samples; by generating many samples at o...
Type hinting a collection of a specified type
...ntainers.
In other words, now you can do:
from typing import List
def my_func(l: List[int]):
pass
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Check/Uncheck checkbox with JavaScript (jQuery or vanilla)?
... about the click method here:
https://developer.mozilla.org/en-US/docs/Web/API/HTMLElement/click
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Can't import my own modules in Python
...s
sys.path.append("..")
from myapp import SomeObject
though that is generally not recommended.
In general, if you want other people to use your Python package, you should use distutils to create a setup script. That way, anyone can install your package easily using a command like python setup.py ...