Overview of Numeric FunctionsΒΆ

Here are some of the numeric functions we might use quite often.

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.

val username = System.getProperty("user.name")

import org.apache.spark.sql.SparkSession

val username = System.getProperty("user.name")
val spark = SparkSession.
    builder.
    config("spark.ui.port", "0").
    config("spark.sql.warehouse.dir", s"/user/${username}/warehouse").
    enableHiveSupport.
    appName(s"${username} | Spark SQL - Predefined Functions").
    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

  • abs - always return positive number

  • sum, avg

  • round - rounds off to specified precision

  • ceil, floor - always return integer.

  • greatest

  • min, max

  • rand

  • pow, sqrt

  • cumedist, stddev, variance

Some of the functions highlighted are aggregate functions, eg: sum, avg, min, max etc.

%%sql

SELECT abs(-10.5), abs(10)

%%sql

USE itversity_retail

%%sql

SHOW tables

%%sql

SELECT order_item_order_id, order_item_subtotal FROM order_items
WHERE order_item_order_id = 2

%%sql

SELECT avg(order_item_subtotal) AS order_revenue_avg FROM order_items
WHERE order_item_order_id = 2

%%sql

SELECT order_item_order_id, 
    avg(order_item_subtotal) AS order_revenue_avg 
FROM order_items
GROUP BY order_item_order_id
LIMIT 10

%%sql

SELECT order_item_order_id, 
    sum(order_item_subtotal) AS order_revenue_sum
FROM order_items
GROUP BY order_item_order_id
LIMIT 10

%%sql

SELECT
    round(10.58) rnd,
    floor(10.58) flr,
    ceil(10.58) cl

%%sql

SELECT
    round(10.44) rnd1,
    round(10.44, 1) rnd1,
    round(10.46, 1) rnd2,
    floor(10.44) flr,
    ceil(10.44) cl

%%sql

SELECT avg(order_item_subtotal) AS order_revenue_avg FROM order_items
WHERE order_item_order_id = 2

%%sql

SELECT round(avg(order_item_subtotal), 2) AS order_revenue_avg 
FROM order_items
WHERE order_item_order_id = 2

%%sql

SELECT order_item_order_id, 
    round(avg(order_item_subtotal), 2) AS order_revenue_avg 
FROM order_items
GROUP BY order_item_order_id
LIMIT 10

%%sql

SELECT order_item_order_id, 
    round(sum(order_item_subtotal), 2) AS order_revenue_sum
FROM order_items
GROUP BY order_item_order_id
LIMIT 10

%%sql

SELECT greatest(10, 11, 13, -13)

%%sql

SELECT rand() AS rand

%%sql

SELECT cast(round(rand() * 1) AS int) AS random_int

%%sql

SELECT order_item_order_id, 
    round(sum(order_item_subtotal), 2) AS order_revenue_sum,
    min(order_item_subtotal) AS order_item_subtotal_min,
    max(order_item_subtotal) AS order_item_subtotal_max 
FROM order_items
GROUP BY order_item_order_id
LIMIT 10

%%sql

SELECT order_item_order_id, order_item_subtotal
FROM order_items
WHERE order_item_order_id = 2

%%sql

SELECT round(sum(order_item_subtotal), 2) AS order_revenue_sum,
    min(order_item_subtotal) AS order_item_subtotal_min,
    max(order_item_subtotal) AS order_item_subtotal_max 
FROM order_items
WHERE order_item_order_id = 2
Date Manipulation Functions Data Type Conversion