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e8210ab201
Our dependency on Hadoop 3 means we already required Java 8. This just fixes the pom so we are compiling to Java 8 classes. This will also allow us to start using some Java 8 features like lambdas for more concise code. Change-Id: I0a5e4cf3f4171eecf218f6d4dd7cdfece9dc9152 Reviewed-on: http://gerrit.cloudera.org:8080/11351 Reviewed-by: Philip Zeyliger <philip@cloudera.com> Tested-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com>
This is a tool to convert a nested dataset to an unnested dataset. The source and/or
destination can be the local file system or HDFS.
Structs get converted to a column (with a long name). Arrays and Maps get converted to
a table which can be joined with the parent table on id column.
$ mvn exec:java \
-Dexec.mainClass=org.apache.impala.infra.tableflattener.Main \
-Dexec.arguments="file:///tmp/in.parquet,file:///tmp/out,-sfile:///tmp/in.avsc"
$ mvn exec:java \
-Dexec.mainClass=org.apache.impala.infra.tableflattener.Main \
-Dexec.arguments="hdfs://localhost:20500/nested.avro,file://$PWD/unnested"
There are various options to specify the type of input file but the output is always
parquet/snappy.
For additional help, use the following command:
$ mvn exec:java \
-Dexec.mainClass=org.apache.impala.infra.tableflattener.Main -Dexec.arguments="--help"
This is used by testdata/bin/generate-load-nested.sh.