Underlying file still referenced even with `copycols=true`

[abx78]

Hello,

I am getting errors when trying to delete a file loaded with DataFrame(Arrow.Table(…)). It seems that the underlying file is still referenced even when I do it with copycols=true.

n = 1
filename = "$(randstring(12)).arrow"
df = DataFrame(x=rand(n))
Arrow.write("$filename", df)
res1 = DataFrame(Arrow.Table("$filename"); copycols=true)
rm(filename)

This the output:

PS > julia -q --project .\test.jl
ERROR: LoadError: IOError: unlink("iPJQf2OSiQaT.arrow"): permission denied (EACCES)
Stacktrace:
 [1] uv_error
   @ .\libuv.jl:97 [inlined]
 [2] unlink(p::String)
   @ Base.Filesystem .\file.jl:934
 [3] rm(path::String; force::Bool, recursive::Bool)
   @ Base.Filesystem .\file.jl:272
 [4] rm(path::String)
   @ Base.Filesystem .\file.jl:263
 [5] top-level scope
   @ D:\source\COMPILETHIS\test.jl:13
in expression starting at test.jl:13

This happens with Julia 1.6.1, Arrow v1.5.0, Windows 10