Solutions - Problem 3¶
Get all the flights which are departed late but arrived early or on time (IsArrDelayed is NO).
Output should contain - FlightCRSDepTime, UniqueCarrier, FlightNum, Origin, Dest, DepDelay, ArrDelay
FlightCRSDepTime need to be computed using Year, Month, DayOfMonth, CRSDepTime
FlightCRSDepTime should be displayed using yyyy-MM-dd HH:mm format.
Output should be sorted by FlightCRSDepTime and then by the difference between DepDelay and ArrDelay
Also get the count of such flights
Let us start spark context for this Notebook so that we can execute the code provided. You can sign up for our 10 node state of the art cluster/labs to learn Spark SQL using our unique integrated LMS.
from pyspark.sql import SparkSession
import getpass
username = getpass.getuser()
spark = SparkSession. \
builder. \
config('spark.ui.port', '0'). \
config("spark.sql.warehouse.dir", f"/user/{username}/warehouse"). \
enableHiveSupport(). \
appName(f'{username} | Python - Basic Transformations'). \
master('yarn'). \
getOrCreate()
If you are going to use CLIs, you can use Spark SQL using one of the 3 approaches.
Using Spark SQL
spark2-sql \
--master yarn \
--conf spark.ui.port=0 \
--conf spark.sql.warehouse.dir=/user/${USER}/warehouse
Using Scala
spark2-shell \
--master yarn \
--conf spark.ui.port=0 \
--conf spark.sql.warehouse.dir=/user/${USER}/warehouse
Using Pyspark
pyspark2 \
--master yarn \
--conf spark.ui.port=0 \
--conf spark.sql.warehouse.dir=/user/${USER}/warehouse
Reading airtraffic data¶
airtraffic_path = "/public/airtraffic_all/airtraffic-part/flightmonth=200801"
airtraffic = spark. \
read. \
parquet(airtraffic_path)
airtraffic.printSchema()
root
|-- Year: integer (nullable = true)
|-- Month: integer (nullable = true)
|-- DayofMonth: integer (nullable = true)
|-- DayOfWeek: integer (nullable = true)
|-- DepTime: string (nullable = true)
|-- CRSDepTime: integer (nullable = true)
|-- ArrTime: string (nullable = true)
|-- CRSArrTime: integer (nullable = true)
|-- UniqueCarrier: string (nullable = true)
|-- FlightNum: integer (nullable = true)
|-- TailNum: string (nullable = true)
|-- ActualElapsedTime: string (nullable = true)
|-- CRSElapsedTime: integer (nullable = true)
|-- AirTime: string (nullable = true)
|-- ArrDelay: string (nullable = true)
|-- DepDelay: string (nullable = true)
|-- Origin: string (nullable = true)
|-- Dest: string (nullable = true)
|-- Distance: string (nullable = true)
|-- TaxiIn: string (nullable = true)
|-- TaxiOut: string (nullable = true)
|-- Cancelled: integer (nullable = true)
|-- CancellationCode: string (nullable = true)
|-- Diverted: integer (nullable = true)
|-- CarrierDelay: string (nullable = true)
|-- WeatherDelay: string (nullable = true)
|-- NASDelay: string (nullable = true)
|-- SecurityDelay: string (nullable = true)
|-- LateAircraftDelay: string (nullable = true)
|-- IsArrDelayed: string (nullable = true)
|-- IsDepDelayed: string (nullable = true)
airtraffic.select('Year', 'Month', 'DayOfMonth', 'CRSDepTime').show()
+----+-----+----------+----------+
|Year|Month|DayOfMonth|CRSDepTime|
+----+-----+----------+----------+
|2008| 1| 16| 1735|
|2008| 1| 17| 1701|
|2008| 1| 17| 1225|
|2008| 1| 17| 1530|
|2008| 1| 17| 1205|
|2008| 1| 18| 1150|
|2008| 1| 18| 1009|
|2008| 1| 19| 835|
|2008| 1| 20| 1935|
|2008| 1| 20| 830|
|2008| 1| 21| 1640|
|2008| 1| 21| 1204|
|2008| 1| 21| 1935|
|2008| 1| 21| 1830|
|2008| 1| 21| 700|
|2008| 1| 22| 1910|
|2008| 1| 22| 1320|
|2008| 1| 23| 908|
|2008| 1| 23| 1252|
|2008| 1| 23| 635|
+----+-----+----------+----------+
only showing top 20 rows
l = [(2008, 1, 23, 700),
(2008, 1, 10, 1855),
]
df = spark.createDataFrame(l, "Year INT, Month INT, DayOfMonth INT, DepTime INT")
df.show()
+----+-----+----------+-------+
|Year|Month|DayOfMonth|DepTime|
+----+-----+----------+-------+
|2008| 1| 23| 700|
|2008| 1| 10| 1855|
+----+-----+----------+-------+
from pyspark.sql.functions import col, date_format, lpad
df.select("DepTime", lpad('DepTime', 4, "0").alias('DepTime')).show()
+-------+-------+
|DepTime|DepTime|
+-------+-------+
| 700| 0700|
| 1855| 1855|
+-------+-------+
from pyspark.sql.functions import substring, concat, lit
df. \
withColumn(
'FlightCRSDepTime',
concat(
"Year", lit("-"),
lpad("Month", 2, "0"), lit("-"),
lpad("DayOfMonth", 2, "0"), lit(" "),
concat(
substring(lpad("DepTime", 4, "0"), 1, 2),
lit(':'),
substring(lpad("DepTime", 4, "0"), 3, 2)
)
)
). \
show()
+----+-----+----------+-------+----------------+
|Year|Month|DayOfMonth|DepTime|FlightCRSDepTime|
+----+-----+----------+-------+----------------+
|2008| 1| 23| 700|2008-01-23 07:00|
|2008| 1| 10| 1855|2008-01-10 18:55|
+----+-----+----------+-------+----------------+
from pyspark.sql.functions import lit, col, concat, lpad, sum, expr, substring
flightsFiltered = airtraffic. \
filter("IsDepDelayed = 'YES' AND IsArrDelayed = 'NO' AND Cancelled = 0"). \
select(
concat(
"Year", lit("-"),
lpad("Month", 2, "0"), lit("-"),
lpad("DayOfMonth", 2, "0"), lit(" "),
concat(
substring(lpad("CRSDepTime", 4, "0"), 1, 2), lit(':'),
substring(lpad("CRSDepTime", 4, "0"), 3, 2)
)
).alias("FlightCRSDepTime"),
"UniqueCarrier", "FlightNum", "Origin",
"Dest", "DepDelay", "ArrDelay"
). \
orderBy("FlightCRSDepTime", col("DepDelay") - col("ArrDelay")). \
show()
+----------------+-------------+---------+------+----+--------+--------+
|FlightCRSDepTime|UniqueCarrier|FlightNum|Origin|Dest|DepDelay|ArrDelay|
+----------------+-------------+---------+------+----+--------+--------+
|2008-01-01 00:55| DL| 560| LAX| ATL| 15| -4|
|2008-01-01 01:00| AA| 2466| SFO| DFW| 2| -7|
|2008-01-01 03:00| CO| 488| SJU| EWR| 3| -12|
|2008-01-01 04:00| B6| 724| BQN| MCO| 4| -23|
|2008-01-01 05:15| XE| 2140| SLC| IAH| 1| -10|
|2008-01-01 05:25| XE| 2429| MSP| IAH| 1| -4|
|2008-01-01 05:30| XE| 2785| BTR| IAH| 6| 0|
|2008-01-01 05:40| OO| 5793| CIC| SFO| 1| -4|
|2008-01-01 05:40| UA| 422| SEA| DEN| 4| -10|
|2008-01-01 06:00| DL| 970| FLL| ATL| 2| 0|
|2008-01-01 06:00| AA| 1734| SAT| DFW| 2| -1|
|2008-01-01 06:00| MQ| 3191| LAX| SJC| 2| -3|
|2008-01-01 06:00| UA| 1294| PDX| DEN| 2| -3|
|2008-01-01 06:00| UA| 265| ORD| DEN| 2| -5|
|2008-01-01 06:00| AA| 1157| AUS| DFW| 1| -6|
|2008-01-01 06:00| AQ| 441| LAS| OAK| 7| 0|
|2008-01-01 06:00| AA| 802| LAX| DFW| 1| -7|
|2008-01-01 06:00| EV| 4484| DSM| ATL| 3| -7|
|2008-01-01 06:00| AA| 1150| LAS| DFW| 3| -7|
|2008-01-01 06:00| OO| 1985| MKE| ATL| 2| -10|
+----------------+-------------+---------+------+----+--------+--------+
only showing top 20 rows
Getting Count¶
flightsFiltered = airtraffic. \
filter("IsDepDelayed = 'YES' AND IsArrDelayed = 'NO' AND Cancelled = 0"). \
select(concat("Year", lit("-"),
lpad("Month", 2, "0"), lit("-"),
lpad("DayOfMonth", 2, "0"), lit(" "),
lpad("CRSDepTime", 4, "0")
).alias("FlightCRSDepTime"),
"UniqueCarrier", "FlightNum", "Origin",
"Dest", "DepDelay", "ArrDelay"
). \
count()
airtraffic.count()
605659
airtraffic.filter("IsDepDelayed = 'NO' AND Cancelled = 0").count()
340461
flightsFiltered
54233