Joins in R

Outer join: merge(x = df1, y = df2, by = “CustomerId”, all = TRUE)

Left outer: merge(x = df1, y = df2, by = “CustomerId”, all.x=TRUE)

Right outer: merge(x = df1, y = df2, by = “CustomerId”, all.y=TRUE)

Cross join: merge(x = df1, y = df2, by = NULL)