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How important is the order of columns in indexes?
... Also keep in mind, suppose your Index is like the picture above, and your query filters on column1 and column2, but column2 is more unique and what you really want to filter on is actually column2, then its more beneficial to just have a index where column 2 is first. This may seem counte...
Explicitly calling return in a function or not
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Question was: Why is not (explicitly) calling return faster or better, and thus preferable?
There is no statement in R documentation making such an assumption.
The main page ?'function' says:
function( arglist ) expr
return(value)
Is it faster without calling return?
Both function() and re...
How to do paging in AngularJS?
I have a dataset of about 1000 items in-memory and am attempting to create a pager for
this dataset, but I'm not sure on how to do this.
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PHP best way to MD5 multi-dimensional array?
... is two-fold here as (1) json_encode alone performs faster than serialize, and (2) json_encode produces a smaller string and therefore less for md5 to handle.
Edit: Here is evidence to support this claim:
<?php //this is the array I'm using -- it's multidimensional.
$array = unserialize('a:6:{i...
Working copy XXX locked and cleanup failed in SVN
...as needed.
Commit
Another option would be to delete the top level folder and check out again. Hopefully it doesn't come to that though.
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How to create a directory if it doesn't exist using Node.js?
...rectory if it doesn't exist.
It should have full permission for the script and readable by others.
17 Answers
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How do CDI and EJB compare? interact?
I'm having a tough time understanding how the two interact and where the boundary between them lies. Do they overlap? Are there redundancies between them?
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Can I use multiple versions of jQuery on the same page?
...f jQuery to a different alias). How the customer is using jQuery will vary and is outside of my control. Can I safely just use the latter half, or do both libraries need to call noConflict()?
– Bungle
Oct 14 '09 at 15:05
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How do you round a floating point number in Perl?
...f perldoc -q round
Does Perl have a round() function? What about ceil() and floor()?
Trig functions?
Remember that int() merely truncates toward 0. For rounding to a certain number of digits, sprintf() or printf() is usually the easiest
route.
printf("%.3f", 3.1415926535); # prints 3...
Getting random numbers in Java [duplicate]
I would like to get a random value between 1 to 50 in Java.
2 Answers
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