hive - Can we use spark session object without explicitly creating it, if Submit a job by spark-submit -


my question basic, code working fine. not clear these 2 points:

1) when submit pyspark job using spark-submit need create spark session object ? in script:

from pyspark.sql import sparksession,sqlcontext pyspark.conf import sparkconf spark = sparksession \     .builder \     .enablehivesupport() \     .appname("test") \     .getorcreate() print(spark) sqlcontext = sqlcontext(spark)

or can directly access spark session object in script out creating it.

from pyspark.sql import sparksession,sqlcontext pyspark.conf import sparkconf print(spark) -- can ***sc*** not sure using spark-2 sqlcontext = sqlcontext(spark)

and if spark session object available how can add config properties such below or how enable hive support. 

spark = sparksession \ .builder \ .enablehivesupport() \ .config(conf=sparkconf().set("spark.driver.maxresultsize", "2g")) \ .appname("test") \ .getorcreate()

2) approach without using spark-submit can write python code generate spark-session object , use this

my doubt if submit job using spark-submit , creating spark session object mentioned above ending creating 2 spark session ?

it helpful if can explain me added advantage of using spark-submit on step 2 method. , need create spark-session object if invoke job using spark-submit command line

when submit pyspark job using spark-submit need create spark session object?

yes, not needed in case of shells.

my doubt if submit job using spark-submit , creating spark session object mentioned above am ending creating 2 spark session ?

tl,dr; no

if check code have written 

spark = sparksession \   .builder \   .enablehivesupport() \   .config(conf=sparkconf().set("spark.driver.maxresultsize", "2g")) \   .appname("test") \   .getorcreate()

observe getorcreate(), take care of @ time 1 sparksession object (spark) exists.

i recommend create context/session in local , makes code pure(as not depending on other our sources object).


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