See,
There are two ways to convert an RDD to DF in Spark.
toDF()
and createDataFrame(rdd, schema)
I will show you how you can do that dynamically.
toDF()
The toDF()
command gives you the way to convert an RDD[Row]
to a Dataframe. The point is, the object Row()
can receive a **kwargs
argument. So, there is an easy way to do that.
from pyspark.sql.types import Row
#here you are going to create a function
def f(x):
d = {}
for i in range(len(x)):
d[str(i)] = x[i]
return d
#Now populate that
df = rdd.map(lambda x: Row(**f(x))).toDF()
This way you are going to be able to create a dataframe dynamically.
createDataFrame(rdd, schema)
Other way to do that is creating a dynamic schema. How?
This way:
from pyspark.sql.types import StructType
from pyspark.sql.types import StructField
from pyspark.sql.types import StringType
schema = StructType([StructField(str(i), StringType(), True) for i in range(32)])
df = sqlContext.createDataFrame(rdd, schema)
This second way is cleaner to do that…
So this is how you can create dataframes dynamically.