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Which is fastest? SELECT SQL_CALC_FOUND_ROWS FROM `table`, or SELECT COUNT(*)
When you limit the number of rows to be returned by a SQL query, usually used in paging, there are two methods to determine the total number of records:
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Default constructor with empty brackets
... reason that an empty set of round brackets (parentheses) isn't valid for calling the default constructor in C++?
9 Answers...
LEFT OUTER JOIN in LINQ
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This answer is actually helpful. Thank you for actually offering syntax that is understandable.
– Chris Marisic
Oct 23 '14 at 15:01
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How to connect to Mysql Server inside VirtualBox Vagrant?
I mounted a new VirtualBox Machine with Vagrant, and inside that VM I installed Mysql Server. How can I connect to that server outside the vm? I already forward the port 3306 of the Vagrantfile , but when I try to connect to the mysql server, it`s resposts with the error:
'reading initial communica...
GitHub “fatal: remote origin already exists”
...me or update the existing one if you don't need it:
To add a new remote, called for example github instead of origin (which obviously already exists in your system), do the following:
$ git remote add github git@github.com:ppreyer/first_app.git
Remember though, everywhere in the tutorial you see...
How to split a dos path into its components in Python
...y path straight to damnation. They won't realise until one day everything falls to pieces, and they -- or, more likely, somebody else -- has to work out why everything has gone wrong, and it turns out somebody made a filename that mixes slashes and backslashes -- and some person suggests that the an...
Mozilla PDF.js：PDF在线预览 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...What browsers are supported?支持哪些浏览器?
The goal is to support all HTML5 compliant browsers, but sincefeature support varies per browser/version our support for all PDF featuresvaries as well. If you want to support more browsers than Firefox you'll needto include compatibility.jswhich h...
What is the rationale behind having companion objects in Scala?
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The companion object basically provides a place where one can put "static-like" methods. Furthermore, a companion object, or companion module, has full access to the class members, including private ones.
Companion objects are great for encapsulating...
minimum double value in C/C++
Is there a standard and/or portable way to represent the smallest negative value (e.g. to use negative infinity) in a C(++) program?
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How to round up the result of integer division?
...ause it only uses it once, you don't need to store the recordsPerPage specially if it comes from an expensive function to fetch the value from a config file or something.
I.e. this might be inefficient, if config.fetch_value used a database lookup or something:
int pageCount = (records + config.f...