Based on the CRAN check results for ROracle, it looks like there's an issue with installing the package in the release version of R (3.5.0).
It doesn't look like the package is on GitHub, and there's not a link for reporting issues/bugs, but I think this is an issue that will need the package maintainers to step in…
P.S. Does this work in R, but not in the RStudio IDE? If it's not an IDE-dependent issue, could you please move the question to the
#general category (in this case)?