2

When I try to convert by RDD to Dataframe in spark and I get following exception "Can not infer schema for type: "

example:

>> rangeRDD.take(1).foreach(println)
(301,301,10)
>> sqlContext.inferSchema(rangeRDD)
Can not infer schema for type: <type 'unicode'>

Any pointer how to fix it? I even tried injecting schema myself in sqlContext.createDataFrame(rdd, schema) 

schema = StructType([
StructField("x", IntegerType(), True),
StructField("y", IntegerType(), True),
StructField("z", IntegerType(), True)]) 
df = sqlContext.createDataFrame(rangeRDD, schema)
print df.first()

but ended up in runtime error 'ValueError: Unexpected tuple u'(301,301,10)' with StructType'

Improve this question

1 Answer 1

Reset to default
2

Try parsing data first

>>> rangeRDD = sc.parallelize([ u'(301,301,10)'])
>>> tupleRangeRDD = rangeRDD.map(lambda x: x[1:-1]) \
...                        .map(lambda x: x.split(",")) \
...                        .map(lambda x: [int(y) for y in x])
>>> df = sqlContext.createDataFrame(tupleRangeRDD, schema)
>>> df.first()
Row(x=301, y=301, z=10)
Improve this answer
Sign up to request clarification or add additional context in comments.

Comments

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Start asking to get answers

Find the answer to your question by asking.

Ask question

Explore related questions

See similar questions with these tags.