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Subqueries vs joins
...nherited from another company to use an inner join instead of a subquery like:
14 Answers
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CodeIgniter - accessing $config variable in view
Pretty often I need to access $config variables in views.
I know I can pass them from controller to load->view() .
But it seems excessive to do it explicitly.
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Should I use the datetime or timestamp data type in MySQL?
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Timestamps in MySQL are generally used to track changes to records, and are often updated every time the record is changed. If you want to store a specific value you should use a datetime field.
If you meant that you want to decide between using a UNIX timestamp or a na...
C# how to create a Guid value?
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DavidDavid
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How to sum a variable by group
...f you want to aggregate multiple columns, you could use the . notation (works for one column too)
aggregate(. ~ Category, x, sum)
or tapply:
tapply(x$Frequency, x$Category, FUN=sum)
First Second Third
30 5 34
Using this data:
x <- data.frame(Category=factor(c("First", ...
How to break nested loops in JavaScript? [duplicate]
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You should be able to break to a label, like so:
function foo ()
{
dance:
for(var k = 0; k < 4; k++){
for(var m = 0; m < 4; m++){
if(m == 2){
break dance;
}
}
}
}
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How can I read command line parameters from an R script?
I've got a R script for which I'd like to be able to supply several command-line parameters (rather than hardcode parameter values in the code itself). The script runs on Windows.
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Getting the count of unique values in a column in bash
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To see a frequency count for column two (for example):
awk -F '\t' '{print $2}' * | sort | uniq -c | sort -nr
fileA.txt
z z a
a b c
w d e
fileB.txt
t r e
z d a
a g c
fileC.txt
z r a
v d c
a m c
Result:
3 d
2 r
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Generating UML from C++ code? [closed]
...verse engineering of the UML class diagram from C++ code in presence of weakly typed containers (2001) - http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.27.9064
Umbrello UML Modeller - http://uml.sourceforge.net/
A list of other tools to look at - http://plg.uwaterloo.ca/~migod/uml.html
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jQuery remove all list items from an unordered list
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$("ul").empty() works fine. Is there some other error?
$('input').click(function() {
$('ul').empty()
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<ul>
<li>te...