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MySQL with Node.js
I've just started getting into Node.js. I come from a PHP background, so I'm fairly used to using MySQL for all my database needs.
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What is the difference between “def” and “val” to define a function
...if you need a function (not method) for function composition or for higher order functions (like filter(even)) compiler will generate a function from your method every time you are using it as function, so performance could be slightly worse than with val.
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What's the difference between comma separated joins and join on syntax in MySQL? [duplicate]
...same query. If we do mix them, we need to be aware of a difference in the order of precedence.
excerpt from MySQL Reference Manual
https://dev.mysql.com/doc/refman/5.6/en/join.html
INNER JOIN and , (comma) are semantically equivalent in the absence of a join condition: both produce a Cartesian pro...
How do I install Python OpenCV through Conda?
...I ran conda update --all and some libraries required a downgrade to 1.9 in order to run.
– mercergeoinfo
Nov 12 '15 at 9:23
2
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Using PowerShell to write a file in UTF-8 without the BOM
...losed before sending the result through the pipeline. This is necessary in order to be able to write back to the same file (update it in place).
Generally, though, this technique is not advisable for 2 reasons: (a) the whole file must fit into memory and (b) if the command is interrupted, data will ...
Performance of Arrays vs. Lists
...ing the Capacity of the list to the number of items it will hold.
But, in order to figure out if iterating over a List is as fast as iterating over an array, why don't you benchmark it ?
int numberOfElements = 6000000;
List<int> theList = new List<int> (numberOfElements);
int[] theAr...
jQuery validation: change default error message
... required: true,
minlength: 2,
remote: "users.php"
}
},
messages: {
firstname: "Enter your firstname",
lastname: "Enter your lastname",
username: {
required: "Enter a username",
minlength: jQuery.format("Ent...
In pure functional languages, is there an algorithm to get the inverse function?
...x,-x]) [1..] will work, as this runs through the integers in the following order [0,1,-1,2,-2,3,-3, and so on]. Indeed inv (0 : concatMap (\x -> [x,-x]) [1..]) (+1) (-3) promptly returns -4!
The Control.Monad.Omega package can help you run through lists of tuples etcetera in a good way; I'm sure...
Is there a way to suppress warnings in Xcode?
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In order to surpress a warning for an individual file do the following:
select the file in the xcode project.
press get info
go to the page with build options
enter -Wno- to negate a warning:
-Wno-
e.g.
-Wno-unused-pa...
How to read and write into file using JavaScript?
... Also, depending on your situation you could make an ajax call to a php script and dump the data that way. This was useful in my situation where I wanted to store some data generated on the javascript side, but didn't matter how it got there.
– Dustin Graham
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