如何根据不同数据帧的两个ID列的匹配从数据帧列中提取值？

Question

I'm having a little trouble going about this. Basically, I want to extract the values from column MakeText based on the first occurrence of an id match of 2 different dataframes. One dataframe has only unique IDs, whereas the other dataframe has multiple rows of that same ID, hence the clause for the first occurrence. Each unique ID has unique values for MakeText column.

I tried match and merge in r but I have no idea how to extract column values in case of it due to the varying number of rows of the dataframes.

Based on the id of this:

 wb <- spread(data = newdata, 
             key = an,
             value = av)

 names(wb)[1] <- "ID"

 wb <- as.data.frame(wb)
 View(wb)

  Id     BodyColorText
  1.0    blue
  100.0  cyan
  1001.0 red
  1003.0 black

I want to match it to the ID of this:

View(supplierdata)

  Id     MakeText
  1.0    Mercedes
  1.0    Mercedes
  1001.0 Ferrari
  1001.0 Ferrari
  1003.0 Audi

and extract the MakeText column values to concatenate it to the wb dataframe with respect to that ID.

As the number of rows are not equal - wb has 1103 while supplierdata has 20957 - I am finding it hard to do this.

The final output that I am looking for is the 'wb' dataframe to look like:

  Id     BodyColorText MakeText
  1.0    blue          Mercedes
  100.0  cyan          Porsch
  1001.0 red           Ferrari
  1003.0 black         Audi

Help will be much appreciated.

Answer 1

Using dplyr package :

inner_join(wb, distinct(supplierdata), by = 'Id') 

Is that what you are looking for ?

Answer 2

I believe you're looking for left_join .

library(dplyr)

left_join(wb, suplierdata)