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How to export table as CSV with headings on Postgresql?
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COPY products_273 TO '/tmp/products_199.csv' WITH (FORMAT CSV, HEADER);
as described in the manual.
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Performance surprise with “as” and nullable types
...lable types, and I'm adding a section about using the "as" operator, which allows you to write:
10 Answers
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Access denied for user 'root'@'localhost' while attempting to grant privileges. How do I grant privi
... basics. Though of course, that doesn't mean I haven't missed something totally obvious. :-)
13 Answers
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List comprehension: Returning two (or more) items for each item
...bda x: x + 2
>>> g = lambda x: x ** 2
>>> list(chain.from_iterable((f(x), g(x)) for x in range(3)))
[2, 0, 3, 1, 4, 4]
Timings:
from timeit import timeit
f = lambda x: x + 2
g = lambda x: x ** 2
def fg(x):
yield f(x)
yield g(x)
print timeit(stmt='list(chain.from_itera...
Python date string to date object
...<stdin>", line 1, in <module>
File "/usr/local/lib/python2.7/_strptime.py", line 308, in _strptime
format_regex = _TimeRE_cache.compile(format)
File "/usr/local/lib/python2.7/_strptime.py", line 265, in compile
return re_compile(self.pattern(format), IGNORECASE)
File "/usr/...
Storing integer values as constants in Enum manner in java [duplicate]
... }
public int getValue() { return value; }
}
And then you call PAGE.SIGN_CREATE.getValue() to get 0.
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What does it mean for a data structure to be “intrusive”?
...to know about the list it is in, and inform it of changes.
ORM-systems usually revolve around intrusive data structures, to minimize iteration over large lists of objects. For instance, if you retrieve a list of all the employees in the database, then change the name of one of them, and want to sav...
What is the difference between concurrency and parallelism?
What is the difference between concurrency and parallelism?
37 Answers
37
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Angular JS break ForEach
...r for it does not break the forEach loop. It is merly a way to not execute all logic inside the loop.
– Nebulosar
Apr 8 at 13:42
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How can I list all foreign keys referencing a given table in SQL Server?
...highly referenced table in a SQL Server database. How can I get a list of all the foreign key constraints I will need to remove in order to drop the table?
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