# Step $3$: Understand the data using SQL $($via SQLDF$)$

$>$ ############## $5.$ how many accidents happen on Sunday?

$>$ # Use sql to count how many accidents on "Sunday"

$>$ sun$\_$acc $<-$ sqldf$("$SELECT COUNT$(*)$ as sunday$\_$accidents FROM df$1$ WHERE day$\_$of$\_$week $=$ 'Sun'"$)$

Error in $`[.$data.frame$`($data$,$ setdiff$($names$($data$),$ names$($field$\_$types$)))$ :

undefined columns selected