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Copy a file in a sane, safe and efficient way

...ing with the file system: #include <copyfile.h> int copyfile(const char *from, const char *to, copyfile_state_t state, copyfile_flags_t flags); share | improve this answer | ...
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Select where count of one field is greater than one

...clause, for aggregate result comparison. Taking the query at face value: SELECT * FROM db.table HAVING COUNT(someField) > 1 Ideally, there should be a GROUP BY defined for proper valuation in the HAVING clause, but MySQL does allow hidden columns from the GROUP BY... Is this in preparati...
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Adding 'serial' to existing column in Postgres

...int, b text); CREATE TABLE bar (a serial, b text); INSERT INTO foo (a, b) SELECT i, 'foo ' || i::text FROM generate_series(1, 5) i; INSERT INTO bar (b) SELECT 'bar ' || i::text FROM generate_series(1, 5) i; -- blocks of commands to turn foo into bar CREATE SEQUENCE foo_a_seq; ALTER TABLE foo ALTER...
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Understanding recursion [closed]

.... We'll use a binary tree of nodes, but this time the value held will be a character, not a number. Our tree will have a special property, that for any node, its character comes after (in alphabetical order) the character held by its left child and before (in alphabetical order) the character held ...
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In SQL, how can you “group by” in ranges?

...version. Here are the correct versions of both of them on SQL Server 2000. select t.range as [score range], count(*) as [number of occurences] from ( select case when score between 0 and 9 then ' 0- 9' when score between 10 and 19 then '10-19' else '20-99' end as range from scores)...
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Uniq by object attribute in Ruby

What's the most elegant way to select out objects in an array that are unique with respect to one or more attributes? 14 An...
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How to pattern match using regular expression in Scala?

... Some(p.Jo.StartsWith(fn)), Some(p.`.*(\\w)$`.Regexp(lastChar))) => println(s"Match! $fn ...$lastChar") case _ => println("nope") } } share | improve this answer...
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What are carriage return, linefeed, and form feed?

What is the meaning of the following control characters: 12 Answers 12 ...
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Ruby on Rails form_for select field with class

I am beating my head against the wall on this one. I want to make a simple select tag using the f.select tag but nothing I do works. I put an example below: ...
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How to get all options of a select using jQuery?

How can I get all the options of a select through jQuery by passing on its ID? 17 Answers ...