The first step to import data from a SQL database is creating a connection to it. As Filip explained, you need different packages depending on the database you want to connect to. All of these packages do this in a uniform way, as specified in theDBIpackage.
dbConnect() creates a connection between your R session and a SQL database. The first argument has to be aDBIdriverobject, that specifies how connections are made and how data is mapped between R and the database. Specifically for MySQL databases, you can build such a driver with RMySQL::MySQL().
If the MySQL database is a remote database hosted on a server, you'll also have to specify the following arguments in dbConnect():dbname, host, port,user and password. Most of these details have already been provided.
# Load the DBI package
library(DBI)
# Edit dbConnect() call
con <- dbConnect(RMySQL::MySQL(),
dbname = "tweater",
host = "courses.csrrinzqubik.us-east-1.rds.amazonaws.com",
port = 3306,
user = "student",
password = "datacamp")
# Build a vector of table names: tables
tables<-dbListTables(con)
# Display structure of tables
str(tables)
# Import the users table from tweater: users
users<-dbReadTable(con,"users")
# Print users
users
# Get table names
table_names <- dbListTables(con)
# Import all tables
tables <- lapply(table_names, dbReadTable, conn = con)
# Print out tables
tables
