DataFrame join rename multiple columns in join command

General Usage
1

So i want to outerjoin three dataframes and rename their columns at the same time.

Here is the code that I try to do

using DataFramesMeta, Dates, Plots, DataFrames, MarketData, PyCall

start = DateTime(2018,1,1)
IBCI = DataFrame(yahoo(Symbol("IBCI.DE"), YahooOpt(period1 = start)))
IUSA =  DataFrame(yahoo(Symbol("IUSA.DE"), YahooOpt(period1 = start)))
IEMA =  DataFrame(yahoo(Symbol("IEMA.AS"), YahooOpt(period1 = start)))

dollar_portfolio = outerjoin(IBCI[:,[:timestamp, :Open]],
                             IUSA[:,[:timestamp, :Open]],
                             IEMA[:,[:timestamp, :Open]],
                             on=:timestamp, makeunique=true, 
                             renamecols= "IBCI" => "IUSA"=> "IEMA")

This give me the following error

ERROR: LoadError: MethodError: no method matching outerjoin(::DataFrame, ::DataFrame, ::DataFrame; on=:timestamp, makeunique=true, renamecols="IBCI" => ("IUSA" => "IEMA"))
Closest candidates are:
  outerjoin(::AbstractDataFrame, ::AbstractDataFrame, ::AbstractDataFrame...; on, makeunique, validate, matchmissing) at C:\Users\ignac\.julia\packages\DataFrames\BM4OQ\src\join\composer.jl:1044 got unsupported keyword argument "renamecols"
  outerjoin(::AbstractDataFrame, ::AbstractDataFrame; on, makeunique, source, indicator, validate, renamecols, matchmissing) at C:\Users\ignac\.julia\packages\DataFrames\BM4OQ\src\join\composer.jl:1013
Stacktrace:
 [1] kwerr(::NamedTuple{(:on, :makeunique, :renamecols), Tuple{Symbol, Bool, Pair{String, Pair{String, String}}}}, ::Function, ::DataFrame, ::DataFrame, ::DataFrame)
   @ Base .\error.jl:163
 [2] top-level scope

If I only join two of them everything works fine. But I would like to join multiple at the same time. Does anyone knows how I should do this?
Thanks in advance

2

column renaming is only supported if you do outerjoin for two data frames. If you have more than two and want column renaming then either:

  1. rename columns before the operations
  2. do sequential outerjoin of 2 data frames at a time
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