#quick read to see what the file looks like

data <- read.table(file = "household_power_consumption.txt", nrow = 10, head=TRUE)

#load sql package

library("sqldf")

require("sqldf")

#sql statement to get desired rows

SQL <- "SELECT * FROM file WHERE Date = '1/2/2007' OR Date = '2/2/2007'"

file <- "household_power_consumption.txt"

data <- read.csv.sql(file, sql = SQL, sep=";")

data2 <- read.csv.sql(file, sql = SQL, sep=";")

#########################################plot 3#############################################

png("plot3.png", width=480, height=480)

plot(data2$Days, data2$Sub_metering_1, type="l", col="black", ylab="Energy sub mettering", xlab="")

lines(data2$Days, data2$Sub_metering_2, type="l", col="red")

lines(data2$Days, data2$Sub_metering_3, type="l", col="blue")

legend("topright", lty=1,

col=c("black", "red", "blue"),

legend=c("Sub_metering_1", "Sub_metering_2", "Sub_metering_3"))

dev.off()