Provide doc on making the connector available in Jupyter

[functicons]

This was asked on SO.

[mkleinbort]

I was the one that asked the SO question, and the notebook example helped me fix the issue.

It's probably enough to add something like:

---

To run this from within a Dataproc Jupyter instance, be sure to start a Python notebook (Not PySpark) and run:

from pyspark.sql import SparkSession

spark = SparkSession.builder \
  .appName('EDA')\
  .config('spark.jars', 'gs://spark-lib/bigquery/spark-bigquery-latest.jar') \
  .getOrCreate()

You can then load data as a spark dataframe through

s = spark.read \
  .format('bigquery') \
  .option('table', '{_project_}.{_database_}.{_table_name_}') \
  .load()

[mkleinbort]

That said, I'm seeing terrible performance when I try to run anything.

Even something like

s = spark.read.format('bigquery').option('table', 'my_project.all_data.stores').load()
s.take(1)

Is taking minutes... and then crashing.

Also

s.columns

results in a crash.

That said, that's nothing to do with this issue. I'll do some googling and then ask again.

[mkleinbort]

A correction on the above, I ran

%%time
s.columns

And got an answer, but it took ~5minutes. This was not registered by the %%time command which clocked a wall time of 57.5 µs

[mkleinbort]

Just found that changing things to

s = spark.read \
  .format('bigquery') \
  .option('project', '{_project_name_}') \
  .option('table', '{_database_}.{_table_name_}') \
  .load()

resolved many of my issues, though

s.take(1) 

results in

Server Connection Error
Invalid response: 504

Py4JJavaError: An error occurred while calling o119.collectToPython.
: org.apache.spark.SparkException: Job aborted due to stage failure: 
Task 0 in stage 1.0 failed 4 times, most recent failure: Lost task 0.3 in 
stage 1.0 [...]: java.lang.ClassNotFoundException:
com.google.cloud.spark.bigquery.direct.BigQueryPartition

[davidrabinowitz]

https://github.com/GoogleCloudDataproc/spark-bigquery-connector#using-in-jupyter-notebooks