Build Cloud-Native apps with Apache Cassandra

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jrodkelley_194102 asked ·

Getting NPE in the Data Modeling notebook of the week 2 workshop

In trying to complete the Data Modeling workbook for Week 2... I was able to complete the step of "Describe Table" and examine the "schema? However, when I went to the next step and ran the cell I receive a "java.lang.NullPointerException" and am unable then to complete the next step "Points of interest in the data above." I'm new to programming and am sure its something I'm doing wrong.

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I also noticed some of the cells are missing the select statements. View the cell contents and see if it's blank.

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Hi @chucks240_168748,

some of the cells have been left blank on purpose to encourage the users to practice these statements.

Let us know if you have any problems with these practice exercises, we want to help.

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chucks240_168748 answered ·

I had the same issue as above in the data types notebook, and figure out I needed to do the query, but I said to just execute the cell initially.



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thanks, this explains both the error and the solution!

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bettina.swynnerton answered ·

Hi @jrodkelley_194102,

there have been a couple of instances where the first cell is not executed completely. This is the cell where the schema is set up and data is populated into some of the tables, including the table killrvideo.video_recommendations.

Would you try to run this first cell again, and if the problem persists, could you attach a screenshot when you see the NullPointerException, as it would be helpful to see how this presents itself in Studio.

Thanks very much for your help.

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