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Finding duplicate values in a SQL table
...s unpredictable and you need sql_mode=only_full_group_by:
GROUP BY lname ORDER BY showing wrong results;
Which is the least expensive aggregate function in the absence of ANY() (see comments in accepted answer).
Oracle isn't mainstream enough (warning: humour, I don't know about Oracle).
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Fastest Way to Find Distance Between Two Lat/Long Points
... @Quassnoi: A couple corrections: You'll probably want to switch the order of the coordinates to lat, long. Also, longitudinal distances are proportional the cosine of the latitude, not longitude. And you'll want to change it from multiplication to division, so your first coordinate would b...
Why are elementwise additions much faster in separate loops than in a combined loop?
...auses false aliasing stalls in the processor load/store units.
However, in order for false aliasing to occur, there must be a large enough stride between the datasets. This is why you don't see this in region 3.
Region 5:
At this point, nothing fits in the cache. So you're bound by memory bandwidth....
Multiple INSERT statements vs. single INSERT with multiple VALUES
...ried a query consisting entirely of duplicate rows and neither affects the order of the output of the table of the constants (and as you are inserting into a heap time spent sorting would be pointless anyway even if it did).
Moreover if a clustered index is added to the table the plan still shows ...
Git Symlinks in Windows
... "true" NTFS symlinks is that elevated UAC permissions are not required in order for them to be created.
To remove symlinks from submodules, just use git's built-in support for iterating over them:
git submodule foreach --recursive git rm-symlinks
But, for every drastic action like this, a rever...
What does the 'b' character do in front of a string literal?
...ing.
But also used to represent binary data like struct.pack output.
In order to ease the 2.x-to-3.x transition, the b'...' literal syntax was backported to Python 2.6, in order to allow distinguishing binary strings (which should be bytes in 3.x) from text strings (which should be str in 3.x). ...
Java LinkedHashMap get first or last entry
I have used LinkedHashMap because it is important the order in which keys entered in the map.
14 Answers
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After array_filter(), how can I reset the keys to go in numerical order starting at 0
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Return first N key:value pairs from dict
... This answer is no longer correct. Python dicts now preserve insertion order, and this is explicitly documented.
– Konrad Rudolph
Sep 22 at 12:30
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List comprehension with if statement
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You got the order wrong. The if should be after the for (unless it is in an if-else ternary operator)
[y for y in a if y not in b]
This would work however:
[y if y not in b else other_value for y in a]
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