After loading data from Oracle DB to Cassandra via Sqoop, I was able to view my data through both Cassandra and Hive. I was told that while doing so, 2 files would be generated for each, creating space issues. To resolve this, I dropped the table in Hive and created an external table and mapped it to my column family in Cassandra. But I am not able to view any data in the Hive table. I am using Datastax Enterprise 3.0.1. Using Sqoop, I migrated the table 'test' from Oracle DB to a Cassandra column family of the same name in the keyspace 'test_keyspace'. I am able to view the data through cassandra-cli using the command : list test;
Describing the column family in cqlsh gives me the following result:
CREATE TABLE test ( rowkey text PRIMARY KEY, bar text, gump bigint, home text, note text, pay text ) WITH comment='' AND comparator=text AND read_repair_chance=0.100000 AND gc_grace_seconds=864000 AND default_validation=text AND min_compaction_threshold=4 AND max_compaction_threshold=32 AND replication_on_write='true' AND compaction_strategy_class='SizeTieredCompactionStrategy' AND compression_parameters:stable_compression='SnappyCompressor';
The command i am using to create the Hive table is:
CREATE external TABLE test ( rowkey string, bar string, gump string, home string, note string, pay string ) STORED BY 'org.apache.hadoop.hive.cassandra.CassandraStorageHandler' TBLPROPERTIES ( "cassandra.ks.name" = "test_keyspace" );
The table is listed when i type 'show tables' in Hive. But 'select * from test' shows all the values in the table as NULL, except the row key.
Would anyone know a solution?