dplyr left_join missing values

tidyverse
2

Use rows_update()

library(dplyr)

df1 <- data.frame(
    ID = c("1", "2", "3", "4"),
    value = c("A", "B", NA, NA) 
)

df2 <- data.frame(
    ID = c("3", "4"),
    value = c("C", "D") 
)

df1 %>% 
    rows_update(df2, by = "ID")
#>   ID value
#> 1  1     A
#> 2  2     B
#> 3  3     C
#> 4  4     D

Created on 2020-10-13 by the reprex package (v0.3.0)

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