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Which SQL query is faster? Filter on Join criteria or Where clause?
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Performance-wise, they are the same (and produce the same plans)
Logically, you should make the operation that still has sense if you replace INNER JOIN with a LEFT JOIN.
In your very case this will look like this:
SELECT *
FROM TableA a
LEFT JOIN
TableXRef x
ON x.TableAID = ...
PHP: Convert any string to UTF-8 without knowing the original character set, or at least try
I have an application that deals with clients from all over the world, and, naturally, I want everything going into my databases to be UTF-8 encoded.
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Can scrapy be used to scrape dynamic content from websites that are using AJAX?
...and am dipping my hand into building a web-scraper. It's nothing fancy at all; its only purpose is to get the data off of a betting website and have this data put into Excel.
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Get Image size WITHOUT loading image into memory
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As the comments allude, PIL does not load the image into memory when calling .open. Looking at the docs of PIL 1.1.7, the docstring for .open says:
def open(fp, mode="r"):
"Open an image file, without loading the raster data"
There ar...
How do I determine the target architecture of static library (.a) on Mac OS X?
...cutable ppc
Example with archive:
logan:/Users/logan% file /usr/lib/libMallocDebug.a
/usr/lib/libMallocDebug.a: Mach-O universal binary with 2 architectures
/usr/lib/libMallocDebug.a (for architecture i386): current ar archive random library
/usr/lib/libMallocDebug.a (for architecture ppc): ...
unit testing of private functions with mocha and node.js
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If the function is not exported by the module, it cannot be called by test code outside the module. That's due to how JavaScript works, and Mocha cannot by itself circumvent this.
In the few instances where I determined that testing a private function is the right thing to do, what I'...
Does JavaScript have a method like “range()” to generate a range within the supplied bounds?
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@rodfersou FYI: your example is wrong. stop is not actually the stop / end position but count / distance. (no offense, just to make people aware of the typo)
– F Lekschas
Jul 26 '18 at 2:45
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How do I install an R package from source?
...nt me along this great tutorial on webscraping NYtimes with R . I would really love to try it. However, the first step is to installed a package called RJSONIO from source.
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PHP $_SERVER['HTTP_HOST'] vs. $_SERVER['SERVER_NAME'], am I understanding the man pages correctly?
...you either go with that or you check the host name against a white list:
$allowed_hosts = array('foo.example.com', 'bar.example.com');
if (!isset($_SERVER['HTTP_HOST']) || !in_array($_SERVER['HTTP_HOST'], $allowed_hosts)) {
header($_SERVER['SERVER_PROTOCOL'].' 400 Bad Request');
exit;
}
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How can I wait for a thread to finish with .NET?
I've never really used threading before in C# where I need to have two threads, as well as the main UI thread. Basically, I have the following.
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