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Want to find records with no associated records in Rails
... the DISTINCT. Otherwise, I think you'd want to normalize out the data and index in that case. I might do that by creating a friend_ids hstore or serialized column. Then you could say Person.where(friend_ids: nil)
– Unixmonkey
Dec 20 '16 at 16:02
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Best way to replace multiple characters in a string?
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Replacing two characters
I timed all the methods in the current answers along with one extra.
With an input string of abc&def#ghi and replacing & -> \& and # -> \#, the fastest way was to chain together the replacements like this: text.rep...
Oracle: how to UPSERT (update or insert into a table?)
... t (mykey, mystuff)
values ('X', 123);
exception
when dup_val_on_index then
update t
set mystuff = 123
where mykey = 'X';
end;
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Is there a way for multiple processes to share a listening socket?
...POSIX type OS), using fork() will cause the forked child to have copies of all the parent's file descriptors. Any that it does not close will continue to be shared, and (for example with a TCP listening socket) can be used to accept() new sockets for clients. This is how many servers, including Apac...
Specifically, what's dangerous about casting the result of malloc?
Now before people start marking this a dup, I've read all the following, none of which provide the answer I'm looking for:
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How to open multiple pull requests on GitHub
When I open a pull request on GitHub .
All commits since my last request and all new ones are automatically added to this request .
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Why is pow(a, d, n) so much faster than a**d % n?
...was taking so long (> 20 seconds) for midsize numbers (~7 digits). I eventually found the following line of code to be the source of the problem:
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Force Java timezone as GMT/UTC
.../prop-timezone.html
http://publib.boulder.ibm.com/infocenter/iseries/v5r3/index.jsp?topic=%2Frzatz%2F51%2Fadmin%2Freftz.htm
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How to detect that animation has ended on UITableView beginUpdates/endUpdates?
...ates . I am also using beginUpdates/endUpdates when adjusting rowHeight. All these operations are animated by default.
7 ...
What's the better (cleaner) way to ignore output in PowerShell? [closed]
...ad and > $null has about a 0.3% overhead.
Addendum 2017-10-16: I originally overlooked another option with Out-Null, the use of the -inputObject parameter. Using this the overhead seems to disappear, however the syntax is different:
Out-Null -inputObject ($(1..1000) | ?{$_ -is [int]})
And no...