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Array vs. Object efficiency in JavaScript
...an array, too:
var a3 = [];
a3[29938] = "a";
a3[32994] = "b";
It's basically an array with holes in it, because every array does have continous indexing. It's slower than arrays without holes. But iterating manually through the array is even slower (mostly).
This is an object:
var a3 = {};
a3[2...
How do SQL EXISTS statements work?
...hen tries to match this 'true/false' condition with outerquery." is what really cleared it up for me, I keep thinking that's how subqueries work (and many times they do), but what you said makes sense because the subquery relies on the outer query and therefore must be executed once per row
...
Query to list number of records in each table in a database
... i.object_id = p.OBJECT_ID AND i.index_id = p.index_id
INNER JOIN
sys.allocation_units a ON p.partition_id = a.container_id
WHERE
t.NAME NOT LIKE 'dt%' AND
i.OBJECT_ID > 255 AND
i.index_id <= 1
GROUP BY
t.NAME, i.object_id, i.index_id, i.name, p.[Rows]
ORDER BY
o...
How does the socket API accept() function work?
...r IP : Server Port
So while the Server IP and Server Port are constant in all accepted connections, the client side information is what allows it to keep track of where everything is going.
Example to clarify things:
Say we have a server at 192.168.1.1:80 and two clients, 10.0.0.1 and 10.0.0.2.
...
CSS two divs next to each other
...d="narrow">Narrow (200px)</div>
</div>
This is basically just scraping the surface of flexbox. Flexbox can do pretty amazing things.
For older browser support, you can use CSS float and a width properties to solve it.
#narrow {
float: right;
width: 200px;
back...
How can I develop for iPhone using a Windows development machine?
...the old Dell Precision I had at the time :)
There are three routes;
Install OSx86 (aka iATKOS / Kalyway) on a second partition/disk and dual boot.
Run Mac OS X Server under VMWare (Mac OS X 10.7 (Lion) onwards, read the update below).
Use Delphi XE4 and the macincloud service. This is a commercia...
What is sys.maxint in Python 3?
...integer, and I've read to use "sys.maxint" . However, in Python 3 when I call it I get:
6 Answers
...
How can you find out which process is listening on a port on Windows?
...Note Dane's recommendation for TCPView. It looks very useful!
-a Displays all connections and listening ports.
-b Displays the executable involved in creating each connection or listening port. In some cases well-known executables host multiple independent components, and in these cases the sequen...
How to determine the current shell I'm working on
...s to finding the name of the current shell's executable:
Please note that all three approaches can be fooled if the executable of the shell is /bin/sh, but it's really a renamed bash, for example (which frequently happens).
Thus your second question of whether ps output will do is answered with "n...
Remove directory which is not empty
...
There is a module for this called rimraf (https://npmjs.org/package/rimraf). It provides the same functionality as rm -Rf
Async usage:
var rimraf = require("rimraf");
rimraf("/some/directory", function () { console.log("done"); });
Sync usage:
rimr...