The output of showall looks nasty in a HTML capable display like Jupyter or Weave, so instead you can use the LINES environment variable to increase the displayed row count.

using DataFrames

df = DataFrame(A = rand(Int, 100), B = rand(Int, 100))

withenv("LINES" => 20) do
    display(df)
end

There is also a COLUMNS var, see the displaysize function help.

AFAICT to disable the limit altogether you need to change the display context which gets a bit messy and is just generally inadvisable, but here it is anyway

io = IOBuffer()
ioctx = IOContext(io, :limit => false)
show(ioctx, MIME("text/html"), df)
HTML(String(take!(io)))

showall() no longer exists. It was remove in Julia v0.6. So the original answer to this question no longer exists. Now, you can use the following:

show(IOContext(stdout, :limit=>false), subtypes(Any))

Maybe you can check this issue.

Bottom line, instead of showall you can use:

ENV["LINES"]=200

or whatever number of rows you need and simply type df and enter.

Selecting a single row from a data frame returns a DataFrameRow, which is a view of the row in the original data frame. So any changes you make to the DataFrameRow will be reflected in the original data frame:

julia> using DataFrames

julia> df = DataFrame(a=1:3, b=4:6)
3×2 DataFrame
│ Row │ a     │ b     │
│     │ Int64 │ Int64 │
├─────┼───────┼───────┤
│ 1   │ 1     │ 4     │
│ 2   │ 2     │ 5     │
│ 3   │ 3     │ 6     │

julia> dfr = df[2, :]
DataFrameRow
│ Row │ a     │ b     │
│     │ Int64 │ Int64 │
├─────┼───────┼───────┤
│ 2   │ 2     │ 5     │

julia> dfr.b = 100
100

julia> df
3×2 DataFrame
│ Row │ a     │ b     │
│     │ Int64 │ Int64 │
├─────┼───────┼───────┤
│ 1   │ 1     │ 4     │
│ 2   │ 2     │ 100   │
│ 3   │ 3     │ 6     │

Of course, if you just want to change the values of a few entries in a row, you can do that directly without having to first create a DataFrameRow:

julia> df = DataFrame(a=1:3, b=4:6)
3×2 DataFrame
│ Row │ a     │ b     │
│     │ Int64 │ Int64 │
├─────┼───────┼───────┤
│ 1   │ 1     │ 4     │
│ 2   │ 2     │ 5     │
│ 3   │ 3     │ 6     │

julia> df[2, :] = [101, 102]
2-element Array{Int64,1}:
 101
 102

julia> df
3×2 DataFrame
│ Row │ a     │ b     │
│     │ Int64 │ Int64 │
├─────┼───────┼───────┤
│ 1   │ 1     │ 4     │
│ 2   │ 101   │ 102   │
│ 3   │ 3     │ 6     │