How to implement guide with merging multiple data frames using `dplyr::full_join()` resulting in duplicated rows in r
I've been banging my head against this for hours. I'm experiencing a question when trying to merge multiple data frames using `dplyr::full_join()`. I have three data frames: `df1`, `df2`, and `df3`, all of which contain a common column named `ID`. However, when I perform the joins, I end up with duplicated rows in the final output, which I didn't expect. Here’s the code I’m using: ```r library(dplyr) # Example data frames df1 <- data.frame(ID = c(1, 2, 3), Value1 = c('A', 'B', 'C')) df2 <- data.frame(ID = c(2, 3, 4), Value2 = c('D', 'E', 'F')) df3 <- data.frame(ID = c(3, 4, 5), Value3 = c('G', 'H', 'I')) # Merging data frames result <- df1 %>% full_join(df2, by = 'ID') %>% full_join(df3, by = 'ID') print(result) ``` The output I get is: ``` ID Value1 Value2 Value3 1 1 A <NA> <NA> 2 2 B D <NA> 3 3 C E G 4 3 <NA> <NA> H 5 4 <NA> F I 6 5 <NA> <NA> I ``` As you can see, the ID `3` appears twice with different values from the other two data frames, and I expected it to only appear once. I tried using `distinct()` after the join, but that didn't resolve the scenario because it removes duplicates based on all columns, which isn't what I need. Is there a way to merge these data frames without getting duplicated rows for IDs that exist in multiple data frames? Any suggestions or best practices would be greatly appreciated! My development environment is Linux. Am I missing something obvious? Is there a better approach?