ORC is a columnar (column-oriented) storage format for Hadoop.

Columnar Layout	r{1}-c{1} , r{2}-c{1} , r{3}-c{1} , ...	r{1}-c{2} , r{2}-c{2} , r{3}-c{2} , ...	r{1}-c{3} , r{2}-c{3} , r{3}-c{3} , ...

Row-based Layout	r{1}-c{1} , r{1}-c{2} , r{1}-c{3} , ...	r{2}-c{1} , r{2}-c{2} , r{2}-c{3} , ...	r{3}-c{1} , r{3}-c{2} , r{3}-c{3} , ...

See these pages for more details about ORC Tools:
https://orc.apache.org/docs/java-tools.html
http://repo1.maven.org/maven2/org/apache/orc/orc-tools/1.5.4/

- Usage (hadoop): hadoop jar orc-tools-*-uber.jar [--help] [--define X=Y] <command> <args>

- Usage (local): java -jar orc-tools-*-uber.jar [--help] [--define X=Y] <command> <args>

Commands:
meta print the metadata about the ORC file. data print the data from the ORC file. scan scan the ORC file. convert convert CSV and JSON files to ORC. json-schema scan JSON files to determine their schema. key print information about the keys.
orc-tools-*-uber.jar print help when invoked without parameters or with "-help" parameter:
hadoop jar orc-tools-*-uber.jar --help.

To print the help of a specific command use the following syntax:
hadoop jar orc-tools-*-uber.jar COMMAND --help.

Print the metadata about the ORC file.

• Usage:
  $ hadoop jar orc-tools-1.5.4-uber.jar meta --help usage: meta <input> where <input> is the orc file to print its meta data to standard output.
  
• Example:
  $ hadoop jar orc-tools-1.5.4-uber.jar meta hdfs://localhost:8020/test1.orc

Print the data from the ORC file.

• Usage:
  $ hadoop jar orc-tools-1.5.4-uber.jar data --help usage: data <input> where <input> is the orc file to print its data to standard output.
  
• Example:
  $ hadoop jar orc-tools-1.5.4-uber.jar data hdfs://localhost:8020/test1.orc

Scan the ORC file.

• Usage:
  $ hadoop jar orc-tools-1.5.4-uber.jar scan --help usage: scan <input> where <input> is the orc file to scan and print its info to standard output.
  
• Example:
  $ hadoop jar orc-tools-1.5.4-uber.jar scan hdfs://localhost:8020/test1.orc

Convert CSV and JSON files to ORC.

• Usage:
  $ hadoop jar orc-tools-1.5.4-uber.jar convert --help usage: convert <option> <input> where <input> is the csv/json file to convert to orc file.
  Options:
  -e,--escape <arg> | CSV escape character. -h,--help | Provide help. -H,--header <arg> | CSV header lines. -n,--null <arg> | CSV null string. -o,--output <arg> | Output filename. -q,--quote <arg> | CSV quote character. -s,--schema <arg> | The schema to write in to the file. -S,--separator <arg> | CSV separator character. -t,--timestampformat <arg> | Timestamp Format.
  
• Example:
  $ hadoop jar orc-tools-1.5.4-uber.jar convert hdfs://localhost:8020/test1.json -o hdfs://localhost:8020/test1.orc

Scan JSON files to determine their schema.

• Usage:
  $ hadoop jar orc-tools-1.5.4-uber.jar json-schema --help usage: json-schema <option> <input> where <input> is the json file to scan and print its schema to standard output.
  Options:
  -f,--flat | Print types as flat list of types. -h,--help | Provide help. -p,--pretty | Pretty print the schema. -t,--table | Print types as Hive table declaration.
  
• Example:
  $ hadoop jar orc-tools-1.5.4-uber.jar json-schema hdfs://localhost:8020/test1.json