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Aggregate function in an SQL update query?
...INNER JOIN (select field3, sum(field2) as field2Sum
from table2
group by field3) as t2
on t2.field3 = t1.field3
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How can I negate the return-value of a process?
... not command
The '!' operator, whether built-in to your shell or provided by the o/s, is not universally available. It isn't dreadfully hard to write, though - the code below dates back to at least 1991 (though I think I wrote a previous version even longer ago). I don't tend to use this in my sc...
eval command in Bash and its typical uses
...d.
So eval <some command> will first evaluate <some command> (by evaluate here I mean substitute variables, replace escaped characters with the correct ones etc.), and then run the resultant expression once again.
eval is used when you want to dynamically create variables, or to read o...
Set Django IntegerField by choices=… name
...an readable names. Is there in Django a convenient way to set these fields by the human readable name instead of the value?
...
Is the Scala 2.8 collections library a case of “the longest suicide note in history”? [closed]
...refore out in the open.
In fact the functionality of map that's supported by its complicated type is pretty advanced. Consider this:
scala> import collection.immutable.BitSet
import collection.immutable.BitSet
scala> val bits = BitSet(1, 2, 3)
bits: scala.collection.immutable.BitSet = BitSe...
Create UIActionSheet 'otherButtons' by passing in array, not varlist
... imageUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454...
curl: (60) SSL certificate problem: unable to get local issuer certificate
...cert.pem"
Make sure you enclose the path within double quotation marks!!!
By default, the FastCGI process will parse new files every 300 seconds (if required you can change the frequency by adding a couple of files as suggested here https://ss88.uk/blog/fast-cgi-and-user-ini-files-the-new-htaccess/...
jQuery or javascript to find memory usage of page
Is there a way to find out how much memory is being used by a web page, or by my jquery application?
10 Answers
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Grasping the Node JS alternative to multithreading
...ample if you do a non-blocking file system read this is likely implemented by telling a thread from the thread pool to perform a read and set a callback when it's done which means that the read could be happening on a different thread/core while the main node.js program is doing something else.
But...
Why does C++ require a user-provided default constructor to default-construct a const object?
...idered a defect (against all versions of the standard) and it was resolved by Core Working Group (CWG) Defect 253. The new wording for the standard states in http://eel.is/c++draft/dcl.init#7
A class type T is const-default-constructible if
default-initialization of T would invoke a user-provi...