spark sql count(*) query store result

Question

Hello I use Spark with Python, I performed a basic count(*) query on a dataframe as follow

myquery = sqlContext.sql("SELECT count(*) FROM myDF")

Result is

+--------+
|count(1)|
+--------+
|    3469|
+--------+

How can I save this value in order to perform futher operation.

For instance divide 3469 by 24 [whatever 24 means...]

Answer 1

Given that your query returns dataframe as

+-----+
|count|
+-----+
|3469 |
+-----+

You need to get the first (and only) row, and then its (only) field 'count'

count = dataframe.first()['count'] 

Answer 2

Given that you have dataframe as

+-----+
|count|
+-----+
|3469 |
+-----+

You can perform mathematical operation on columns and create new columns or overwrite on the same using .withColumn api

df.withColumn('devided', df.count/24).show(false)

You should get

+-----+------------------+
|count|devided           |
+-----+------------------+
|3469 |144.54166666666666|
+-----+------------------+