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Consistency ℹ️ For technical support, please contact us via email.
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Use different consistency levels

✅ Start cqlsh from node3 since it is the only node running in dc-atlanta:

./node3/bin/cqlsh

✅ Switch to the killrvideo keyspace, set the consistency level to TWO, and run the query again to retrieve the cassandra partition:

Solution 
USE killrvideo;

CONSISTENCY TWO;

SELECT * FROM killrvideo.videos_by_tag WHERE tag = 'cassandra';

The query should error out with the message NoHostAvailable: because you cannot achieve a consistency level of 'TWO' with only one of the two replica nodes online.

✅ Set the consistency level back to ONE and retry the query:

Solution 
CONSISTENCY ONE;

SELECT * FROM killrvideo.videos_by_tag WHERE tag = 'cassandra';

The query should succeed because we still have one replica node available.

✅ Change the consistency level back to TWO:

Solution 
CONSISTENCY TWO;

✅ Run the following statement to insert a new row into the cassandra partition:

INSERT INTO videos_by_tag (tag, added_date, video_id, title)
VALUES ('cassandra', '2020-03-11', uuid(), 'I Love Cassandra');

The write should fail with the error NoHostAvailable: because we still cannot achieve a consistency level of TWO.

✅ Change the consistency level back to ONE and try the INSERT again:

Solution 
CONSISTENCY ONE;

INSERT INTO videos_by_tag (tag, added_date, video_id, title)
VALUES ('cassandra', '2020-03-11', uuid(), 'I Love Cassandra');

✅ Quit cqlsh:

QUIT
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