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Should I store entire objects, or pointers to objects in containers?
... storing pointers into vector can be efficient if used along with a custom allocator for the pointees. The custom allocator has to take care of the cache locality, for example using placement new (see en.wikipedia.org/wiki/Placement_syntax#Custom_allocators).
– amit
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Random alpha-numeric string in JavaScript? [duplicate]
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Iftah
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answered May 23 '12 at 20:13
NimphiousNimphious
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SQL Server SELECT INTO @variable?
... In case if you aren't using the database type that the OP is using, not all support TOP 1 as Adrian mentioned. SQL Server / MS Access use TOP, MySQL uses LIMIT, and Oracle uses ROWNUM. See w3schools.com/sql/sql_top.asp for more information.
– Tyler
Jul 7 '17...
Finding most changed files in Git
...da591031936f35d80e14a42ca7ba4350 It aggregates changes by folder, specifically by each folder in the roles directory for my case but is easily modified to fit your use case.
– Almenon
Nov 22 '19 at 19:26
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Centering a background image, using CSS
...nd-image:url(https://upload.wikimedia.org/wikipedia/commons/thumb/8/8b/Dore_woodcut_Divine_Comedy_01.jpg/481px-Dore_woodcut_Divine_Comedy_01.jpg);
background-repeat:no-repeat;
background-position: center;
background-size: cover;
html{
height:100%
}
body{
background-image:url(https://uplo...
How to get a list of column names on Sqlite3 database?
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PRAGMA table_info(table_name);
will get you a list of all the column names.
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How can I see the SQL that will be generated by a given ActiveRecord query in Ruby on Rails
...query has been issued, but I'm wondering if there is a method that can be called on and ActiveRecord Query.
11 Answers
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Why is SSE scalar sqrt(x) slower than rsqrt(x) * x?
...ill somewhat faster than sqrtss.
edit: If speed is critical, and you're really calling this in a loop for many values, you should be using the vectorized versions of these instructions, rsqrtps or sqrtps, both of which process four floats per instruction.
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How do you run a single test/spec file in RSpec?
...tests — for the one file I'm editing, for example. rake spec executes all the specs. My project is not a Rails project, so rake spec:doc doesn't work.
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How to make a great R reproducible example
...le examples, see the help files of the function you are using. In general, all the code given there fulfills the requirements of a minimal reproducible example: data is provided, minimal code is provided, and everything is runnable. Also look at questions on Stack Overflow with lots of upvotes.
Pro...