While learning DataFrames.jl
I experienced an issue with one of the examples I found in the documentation:
using DataFrames, Query
df = DataFrame(name=["John", "Sally", "Roger"], age=[54., 34., 79.], children=[0, 2, 4])
@from i in df begin
@where i.name > "John"
@select {i.name}
@collect DataFrame
end
@from i in df begin
@where get(i.name) > "John"
@select {i.name}
@collect DataFrame
end
The first query results in the following error: ERROR: MethodError: no method matching isless(::String, ::Nullable{String})
and it can be made behave correctly (see second query) by using get(i.name)
instead of i.name
.
Is this behavior to be expected or is isless(::String, ::Nullable{String})
missing?