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How many String objects will be created when using a plus sign?

...catenating in a loop. E.g. How many string objects does the following code allocate: string s = ""; for (int i = 0; i < n; i++) s += "a"; – Joren Feb 3 '12 at 20:08 1 ...
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Does Ruby regular expression have a not match operator like “!~” in Perl?

... you can easily negate. According to the release notes, it does even fewer allocations than !~ – panmari May 28 '18 at 20:52 ...
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How do I create a parameterized SQL query? Why Should I?

...ple would do this through a server side programming language library, like PHP's PDO or Perl DBI. For instance, in PDO: $dbh=pdo_connect(); //you need a connection function, returns a pdo db connection $sql='insert into squip values(null,?,?)'; $statement=$dbh->prepare($sql); $data=array('my...
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Split a List into smaller lists of N size

...memory? Each time locations.Skip.ToList happens I wonder if more memory is allocated and unskipped items are referenced by a new list. – Zasz Feb 12 '14 at 7:40 ...
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What is the difference between an Azure Web Site and an Azure Web Role

...mmand-line tools to set up a web site with popular languages such as .NET, PHP, Node.js, and Python. Supported frameworks are already deployed and do not require more installation steps. The Azure Web Sites gallery contains many third-party applications, such as Drupal and WordPress as well as devel...
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Is if(items != null) superfluous before foreach(T item in items)?

...can matter. For most code we should choose the idiomatic code. But the two allocations you mentioned will be a performance problem in even fewer cases. – CodesInChaos Jun 23 '11 at 15:22 ...
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Why does .NET foreach loop throw NullRefException when collection is null?

... either return an empty collection — it is a call to constructor, memory allocation, and perhaps a bunch of a code to be executed. Either you could just return «null» → obviously there's only a code to return and a very short code to check is the argument is «null». It's just a performance. ...
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Howto: Clean a mysql InnoDB storage engine?

...t store deleted data. As you insert and delete rows, unused space is left allocated within the InnoDB storage files. Over time, the overall space will not decrease, but over time the 'deleted and freed' space will be automatically reused by the DB server. You can further tune and manage the space...
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What is this Javascript “require”?

... The equivalent in PHP would be include/require[_once] (php.net link), not use, which is an aliasing keyword. – nevvermind Apr 2 '19 at 12:39 ...
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Having links relative to root?

...tml#h-12.4. Suggested reading: http://www.motive.co.nz/glossary/linking.php http://www.communitymx.com/content/article.cfm?cid=AEDCC52C4AD230AD share | improve this answer | ...