[R-Forge #5672] error when merging zero row data.table

[arunsrinivasan]

Submitted by: Garrett See; Assigned to: Arun ; R-Forge link

The following did not give an error in 1.9.2, but does in 1.9.3. Using svn revision 1263:

library(data.table)
# data.table 1.9.3  For help type: help("data.table")
a <- data.table(BOD, key="Time")
b <- data.table(BOD, key="Time")[Time < 0] # zero row data.table
merge(a,b, all=TRUE) # works fine
#    Time demand.x demand.y
#1:    1      8.3       NA
#2:    2     10.3       NA
#3:    3     19.0       NA
#4:    4     16.0       NA
#5:    5     15.6       NA
#6:    7     19.8       NA
merge(b,a, all=TRUE) # error
# Error in setcolorder(dt, c(setdiff(names(dt), end), end)) :
#   neworder is length 2 but x has 3 columns.

Originally reported on the mailing list