9  Combine datasets in dplyr

How to use mutating joins to merge data

Abstract

This chapter teaches researchers how to combine datasets.

Keywords

dplyr, merge data

Tip📖 dplyr resources

• Mutate Joins
• Documentation
• R4DS Book Chapter 3
• R4DS Ch. 12 - 19
• Datacamp
• Interactive Cheatsheet
• PDF Cheatsheet

```{r}
library(readxl)
library(dplyr)
# source: https://dplyr.tidyverse.org/reference/mutate-joins.html

# Read your Excel files
primary_data <- read_excel("primary_file.xlsx")
secondary_data <- read_excel("secondary_file.xlsx")

# Select only the variables you need from secondary dataset, then join
combined <- primary_data %>%
  left_join(
    secondary_data %>% select(PASSWORD, SLEEPSCORE1, SLEEPSCORE2, SLEEPSCORE3),
    by = "PASSWORD"
  )
  
```