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Python Create unix timestamp five minutes in the future
...'s comment enough. If you're trying to get a UNIX timestamp (and therefore one in UTC), use calendar.timegm.
– Bialecki
Feb 20 '13 at 20:58
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Why are joins bad when considering scalability?
...don't need to in volume, and the things you actually do you make sure are done as efficiently as possible.
In that context, of course joining two separate data sources is relatively slow, at least compared to not joining them, because it's work you need to do live at the point where the user request...
Regex lookahead, lookbehind and atomic groups
... What do you mean by "finds the second bar" part? There is only one bar in the expression/string. Thanks
– ziggy
Feb 8 '14 at 11:22
3
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How can I get the client's IP address in ASP.NET MVC?
... ..
}
}
}
BUT, if the request has been passed on by one, or more, proxy servers then the IP address returned by HttpRequest.UserHostAddress property will be the IP address of the last proxy server that relayed the request.
Proxy servers MAY use the de facto standard of placin...
Difference between a “coroutine” and a “thread”?
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Coroutines are a form of sequential processing: only one is executing at any given time (just like subroutines AKA procedures AKA functions -- they just pass the baton among each other more fluidly).
Threads are (at least conceptually) a form of concurrent processing: multip...
EF Migrations: Rollback last applied migration?
...le migrations
PM> Update-Database -TargetMigration:"CategoryIdIsLong"
One solution would be to create a wrapper PS script that automates the steps above. Additionally, feel free to create a feature request for this, or better yet, take a shot at implementing it! https://github.com/dotnet/ef6
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Good examples of Not a Functor/Functor/Applicative/Monad?
While explaining to someone what a type class X is I struggle to find good examples of data structures which are exactly X.
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python list in sql query as parameter
...t up the list l, then use tuple, then pass the tuple into the query. well done.
– MEdwin
Nov 13 '18 at 10:25
12
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How do I (or can I) SELECT DISTINCT on multiple columns?
...ND s1.ctid <> s.ctid
Every table should have a primary key. Add one if you didn't have one, yet. I suggest a serial or an IDENTITY column in Postgres 10+.
Related:
In-order sequence generation
Auto increment table column
How is this faster?
The subquery in the EXISTS anti-semi-join ...
How do I calculate the normal vector of a line segment?
...(x', y') = (-y, x) and (x', y') = (y, -x) seems to be right, but why would one use dx and dy here. Moreover, based on slopes, m1 * m2 = -1 for right angle lines, hence dy' = dx' * (-dx/dy) and dx' = dy' * (-dy/dx), how come in your equation normal.x = x' = -dy?
– legends2k
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