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MySQL > Table doesn't exist. But it does (or it should)
...e table name I'm using is off. So table is called 'db' but I used 'DB' in select statement. Make sure the case is the same.
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Alternate output format for psql
...e a table with columns c1 through cN . The columns are wide enough that selecting all columns causes a row of query results to wrap multiple times. Consequently, the output is hard to read.
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How to uncheck a radio button?
...nt need the each function; you could just chain the removeAttr call to the selector.
– cjstehno
Jan 22 '10 at 13:55
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Undo git pull, how to bring repos to old state
...unning "gitk --all from your git command line"), it's simple. Just run it, select the commit you want to rollback to (right-click), and select "Reset master branch to here". If you have no uncommited changes, chose the "hard" option.
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Pass a data.frame column name to a function
...(x[,column])
}
fun1(df, "B", max)
Alternatively, using [[ also works for selecting a single column at a time:
df <- data.frame(A=1:10, B=2:11, C=3:12)
fun1 <- function(x, column){
max(x[[column]])
}
fun1(df, "B")
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How can I delete all unversioned/ignored files/folders in my working copy?
...ovides a finer grain resolution than Stefan's answer provided, letting you select non-versioned files separately from ignored files. Just select TortoiseSvn >> Clean up... to open this dialog.
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Trimming a huge (3.5 GB) csv file to read into R
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My try with readLines. This piece of a code creates csv with selected years.
file_in <- file("in.csv","r")
file_out <- file("out.csv","a")
x <- readLines(file_in, n=1)
writeLines(x, file_out) # copy headers
B <- 300000 # depends how large is one pack
while(length(x)) {
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Cannot open backup device. Operating System error 5
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Go to the SQL server folder in start menu and click configuration tools
Select SQL Server configuration manager
On SQL server services, on the desired instance change the (Log On as) to local system
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Split output of command by columns using Bash?
...d> | while read a b; do echo $a; done
The first parameter to read, a, selects the first column, and if there is more, everything else will be put in b. As a result, you never need more variables than the number of your column +1.
So,
while read a b c d; do echo $c; done
will then output th...
How to reshape data from long to wide format
...mes(df) <- unique(dat1$name)
df
sqldf package:
library(sqldf)
sqldf('SELECT name,
MAX(CASE WHEN numbers = 1 THEN value ELSE NULL END) x1,
MAX(CASE WHEN numbers = 2 THEN value ELSE NULL END) x2,
MAX(CASE WHEN numbers = 3 THEN value ELSE NULL END) x3,
MAX(CASE WHEN numbe...