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Why is iterating through a large Django QuerySet consuming massive amounts of memory?
...lling out.
From my reading of the docs, iterator() does nothing more than bypass QuerySet's internal caching mechanisms. I think it might make sense for it to a do a one-by-one thing, but that would conversely require ten-million individual hits on your database. Maybe not all that desirable.
It...
Windows equivalent to UNIX pwd
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Why do you need to echo? Just cd by itself seems to work fine.
– Kevin Workman
Feb 7 '18 at 5:20
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Which is faster/best? SELECT * or SELECT column1, colum2, column3, etc
...ogging, effective/expiration dates and other similar things that get added by DBAs for systemically for compliance issues. Another source of underhanded changes is denormalizations for performance elsewhere in the system or user-defined fields.
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How do negative margins in CSS work and why is (margin-top:-5 != margin-bottom:5)?
... studying the spec.
For instance, rendering of your sample code is guided by the css spec as described in calculating heights and margins for absolutely positioned non-replaced elements.
If I were to make a graphical representation, I'd probably go with something like this (not to scale):
The m...
Difference between UIViewContentModeScaleAspectFit and UIViewContentModeScaleToFill?
...wContentModeScaleToFill
Scales the content to fit the size of itself by changing the aspect ratio of the content if necessary.
UIViewContentModeScaleAspectFit
Scales the content to fit the size of the view by maintaining the aspect ratio. Any remaining area of the view’s bounds is tr...
What does the caret operator (^) in Python do?
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I wanted to add, you can do binary numbers by typing 0bX where X is your binary. 0b0001, 0b0010, etc. So, 0b1101 ^ 0b1110 would give you 0b0011 (or 3).
– Jeff
Jul 28 '15 at 23:58
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Format a date using the new date time API
...lds. The natural consequence is that not every possible field is supported by every type (and users can even define their own specialized fields). It is also possible to programmatically ask every object of type TemporalAccessor for its specific set of supported fields. For LocalDate we find:
•DA...
How to link to specific line number on github
... the important part:
Now get the canonical url for that particular commit by pressing the y key. The URL in your browser will change to become something like this:
https://github.com/git/git/blob/5bdb7a78adf2a2656a1915e6fa656aecb45c1fc3/README#L18-L20
That link contains the actual SHA hash for t...
Handling warning for possible multiple enumeration of IEnumerable
... an expensive object. Your method signature doesn't indicate either way.
By changing the method signature to IList/ICollection, you will at least make it clearer to the caller what your expectations are, and they can avoid costly mistakes.
Otherwise, most developers looking at the method might a...
Python Threading String Arguments
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Second, A quirk in Python about tuple:
Empty tuples are constructed by an empty pair of parentheses; a tuple with one item is constructed by following a value with a comma (it is not sufficient to enclose a single value in parentheses).
On the other hand, a string is a sequence of character...