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Create a unique number with javascript time
...oString(36) + Math.random().toString(36).substr(2) That will give you a 19 character alphanumeric string which is a decent amount of entropy. Albeit half of it is predictable.
– Erik Pukinskis
Jul 30 '17 at 23:32
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PostgreSQL query to return results as a comma separated list
Let say you have a SELECT id from table query (the real case is a complex query) that does return you several results.
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Resolve build errors due to circular dependency amongst classes
...;<endl;
}
//main.cpp
#include "A.h"
#include "B.h"
int main(int argc, char* argv[])
{
A a(10);
B b(3.14);
a.Print();
a.SetB(&b);
b.Print();
b.SetA(&a);
return 0;
}
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JPG vs. JPEG image formats
...ut it is inaccurate. • The JPEG group were mostly Unix shops, thus the 4-char .jpeg extension, not because of Mac. • It was the DOS 8.3 limit that caused the shortening to .jpg — windows was just a shell on top of DOS. • The commonly accepted .jpg form is because of programs that had to cope...
What is the fastest/most efficient way to find the highest set bit (msb) in an integer in C?
...ruction.)
Example code for gcc:
#include <iostream>
int main (int,char**)
{
int n=1;
for (;;++n) {
int msb;
asm("bsrl %1,%0" : "=r"(msb) : "r"(n));
std::cout << n << " : " << msb << std::endl;
}
return 0;
}
See also this inline assembler tutoria...
How to change max_allowed_packet size
...ices.msc, Enter
You could find an entry like 'MySQL56', right click on it, select properties
You could see sth like "D:/Program Files/MySQL/MySQL Server 5.6/bin\mysqld" --defaults-file="D:\ProgramData\MySQL\MySQL Server 5.6\my.ini" MySQL56
I got this answer from http://bugs.mysql.com/bug.php?id=68...
Sql Server equivalent of a COUNTIF aggregate function
...u could use a SUM (not COUNT!) combined with a CASE statement, like this:
SELECT SUM(CASE WHEN myColumn=1 THEN 1 ELSE 0 END)
FROM AD_CurrentView
Note: in my own test NULLs were not an issue, though this can be environment dependent. You could handle nulls such as:
SELECT SUM(CASE WHEN ISNULL(myC...
How to enter quotes in a Java string?
...you didn't specify), but you should be able to "escape" the quotation mark character with a backslash: "\"ROM\""
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Counting the number of option tags in a select tag in jQuery
How do I count the number of <option> s in a <select> DOM element using jQuery?
8 Answers
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Split column at delimiter in data frame [duplicate]
...OO=c('a|b','b|c','x|y'))
foo <- data.frame(do.call('rbind', strsplit(as.character(df$FOO),'|',fixed=TRUE)))
Or, if you want to replace the columns in the existing data.frame:
within(df, FOO<-data.frame(do.call('rbind', strsplit(as.character(FOO), '|', fixed=TRUE))))
Which produces:
ID ...