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SQL how to make null values come last when sorting ascending
... the sort column to improve performance(*), then this method will somewhat complicate the query plan and lose much of the performance benefit. * - indexes provided the data presorted, hence avoiding a sort per query execution. It's advisable to filter out the NULL records if possible to avoid this i...
How do you find the sum of all the numbers in an array in Java?
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How to calculate the angle between a line and the horizontal axis?
...tion:
angleInDegrees = atan2(deltaY, deltaX) * 180 / PI
EDIT (Feb. 22, 2017): In general, however, calling atan2(deltaY,deltaX) just to get the proper angle for cos and sin may be inelegant. In those cases, you can often do the following instead:
Treat (deltaX, deltaY) as a vector.
Normalize th...
How do I translate an ISO 8601 datetime string into a Python datetime object? [duplicate]
...ng a datetime string in a format like "2009-05-28T16:15:00" (this is ISO 8601, I believe). One hackish option seems to be to parse the string using time.strptime and passing the first six elements of the tuple into the datetime constructor, like:
...
Why is an int in OCaml only 31 bits?
...th=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4...
How do I declare class-level properties in Objective-C?
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stackoverflow.com/questions/554969/…
– Undistraction
May 8 '12 at 19:42
60
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Quickly reading very large tables as dataframes
...t nrows=the number of records in your data (nmax in scan).
Make sure that comment.char="" to turn off interpretation of comments.
Explicitly define the classes of each column using colClasses in read.table.
Setting multi.line=FALSE may also improve performance in scan.
If none of these thing wo...
How can I clear event subscriptions in C#?
...you're stubborn, you can force it clear via reflection. See stackoverflow.com/questions/91778/… .
– Brian
Oct 29 '10 at 21:36
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How to Batch Rename Files in a macOS Terminal?
... An example using matched replacements (.* -> $1), e.g. Rename Foo bar S01E01 biz baz.ext to S01E01.ext: rename -n -e 's/.*(S[0-9]{2}E[0-9]{2}).*(\.[a-z]{2,4})/$1$2/' *
– Steve Robbins
Jan 6 '16 at 7:48
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Select SQL Server database size
... , backup_size =
CAST(CASE WHEN s.backup_size = s.compressed_backup_size
THEN s.backup_size
ELSE s.compressed_backup_size
END / 1048576.0 AS DECIMAL(18,2))
, RowNum = ...