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Ternary Operator Similar To ?:
... answered Feb 9 '11 at 19:06
LandeiLandei
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...
Reference alias (calculated in SELECT) in WHERE clause
...x (or costly to calculate) you should probably consider a computed column (and perhaps persisted) instead, especially if a lot of queries refer to this same expression.
PS your fears seem unfounded. In this simple example at least, SQL Server is smart enough to only perform the calculation once, ev...
Function to calculate distance between two coordinates
I'm currently using the function below and it doesn't work properly. According to Google Maps, the distance between these coordinates (from 59.3293371,13.4877472 to 59.3225525,13.4619422 ) are 2.2 kilometres while the function returns 1.6 kilometres. How can I make this function return the ...
Difference between `mod` and `rem` in Haskell
What exactly is the difference between mod and rem in Haskell?
4 Answers
4
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What do hjust and vjust do when making a plot using ggplot?
...lot using ggplot, I spend a little while trying different values for hjust and vjust in a line like
2 Answers
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Define all functions in one .R file, call them from another .R file. How, if possible?
...If abc.R is:
fooABC <- function(x) {
k <- x+1
return(k)
}
and xyz.R is:
fooXYZ <- function(x) {
k <- fooABC(x)+1
return(k)
}
then this will work:
> source("abc.R")
> source("xyz.R")
> fooXYZ(3)
[1] 5
>
Even if there are cyclical dependencies, this wi...
SQL Logic Operator Precedence: And and Or
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And has precedence over Or, so, even if a <=> a1 Or a2
Where a And b
is not the same as
Where a1 Or a2 And b,
because that would be Executed as
Where a1 Or (a2 And b)
and what you want, to make them the same,...
For loop example in MySQL
...ile v_counter < v_max do
insert into foo (val) values ( floor(0 + (rand() * 65535)) );
set v_counter=v_counter+1;
end while;
commit;
end #
delimiter ;
call load_foo_test_data();
select * from foo order by id;
...
Scala: Nil vs List()
In Scala, is there any difference at all between Nil and List() ?
3 Answers
3
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How to get a vertical geom_vline to an x-axis of class date?
Even though I found Hadley's post in the google group on POSIXct and geom_vline , I could not get it done. I have a time series from and would like to draw a vertical line for years 1998, 2005 and 2010 for example. I tried with ggplot and qplot syntax, but still I either see no vertical line ...