## -----------------------------------------------------------------------------
knitr::opts_chunk$set(collapse = TRUE, comment = "#>")
options(tibble.print_min = 6L, tibble.print_max = 6L, digits = 3)

## ----message = FALSE----------------------------------------------------------
library(dbplyr)
library(dplyr)

con <- DBI::dbConnect(RSQLite::SQLite(), ":memory:")
flights <- copy_to(con, nycflights13::flights)
airports <- copy_to(con, nycflights13::airports)

## -----------------------------------------------------------------------------
flights |>
  select(contains("delay")) |>
  show_query()

flights |>
  select(distance, air_time) |>  
  mutate(speed = distance / (air_time / 60)) |>
  show_query()

## -----------------------------------------------------------------------------
flights |> 
  filter(month == 1, day == 1) |>
  show_query()

## -----------------------------------------------------------------------------
flights |> 
  arrange(carrier, desc(arr_delay)) |>
  show_query()

## -----------------------------------------------------------------------------
flights |>
  group_by(month, day) |>
  summarise(delay = mean(dep_delay, na.rm = TRUE)) |>
  show_query()

## -----------------------------------------------------------------------------
flights |>
  select(distance, air_time) |>  
  mutate(
    air_time_h = air_time / 60,
    speed = distance / air_time_h) |>
  show_query()

## -----------------------------------------------------------------------------
flights |>
  select(distance, air_time) |>  
  mutate(
    air_time_h = air_time / 60,
    speed = distance / air_time_h) |>
  show_query(sql_options = sql_options(cte = TRUE))