[CASSANDRA-3371] Cassandra inferred schema and actual data don't match

• Type: Bug
• Status: Resolved
• Priority: Normal
• Resolution: Fixed
• Fix Version/s: 1.0.8
• Severity: Normal
• Assignee: Brandon Williams
• Reporter: Pete Warden

Authors

Brandon Williams

Reviewers

Pavel Yaskevich

• Created: 17/Oct/11 10:25
• Updated: 16/Apr/19 09:32
• Resolved: 13/Feb/12 23:45

Description

It's looking like there may be a mismatch between the schema that's being reported by the latest CassandraStorage.java, and the data that's actually returned. Here's an example:

rows = LOAD 'cassandra://Frap/PhotoVotes' USING CassandraStorage();
DESCRIBE rows;
rows: {key: chararray,columns: {(name: chararray,value: bytearray,photo_owner: chararray,value_photo_owner: bytearray,pid: chararray,value_pid: bytearray,matched_string: chararray,value_matched_string: bytearray,src_big: chararray,value_src_big: bytearray,time: chararray,value_time: bytearray,vote_type: chararray,value_vote_type: bytearray,voter: chararray,value_voter: bytearray)}}
DUMP rows;
(691831038_1317937188.48955,

{(photo_owner,1596090180),(pid,6855155124568798560),(matched_string,),(src_big,),(time,Thu Oct 06 14:39:48 -0700 2011),(vote_type,album_dislike),(voter,691831038)}

)

getSchema() is reporting the columns as an inner bag of tuples, each of which contains 16 values. In fact, getNext() seems to return an inner bag containing 7 tuples, each of which contains two values.

It appears that things got out of sync with this change:
http://svn.apache.org/viewvc/cassandra/branches/cassandra-0.8/contrib/pig/src/java/org/apache/cassandra/hadoop/pig/CassandraStorage.java?r1=1177083&r2=1177082&pathrev=1177083

See more discussion at:
http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/pig-cassandra-problem-quot-Incompatible-field-schema-quot-error-tc6882703.html

Issue Links

• is blocked by: PIG-2485 Unable to find alias in a bag with nested schema
• is duplicated by: CASSANDRA-3745 contrib/PIG example fails when column metadata exists for CF