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