gpmapreduce

Runs Greenplum MapReduce jobs as defined in a YAML specification document.

Synopsis

gpmapreduce -f <config.yaml> [dbname [<username>]] 
     [-k <name=value> | --key <name=value>] 
     [-h <hostname> | --host <hostname>] [-p <port>| --port <port>] 
     [-U <username> | --username <username>] [-W] [-v]
gpmapreduce -x | --explain 
gpmapreduce -X | --explain-analyze
gpmapreduce -V | --version 
gpmapreduce -h | --help

Requirements

The following are required prior to running this program:

• You must have your MapReduce job defined in a YAML file. See gpmapreduce.yaml for more information about the format of, and keywords supported in, the Greenplum MapReduce YAML configuration file.
• You must be a Greenplum Database superuser to run MapReduce jobs written in untrusted Perl or Python.
• You must be a Greenplum Database superuser to run MapReduce jobs with EXEC and FILE inputs.
• You must be a Greenplum Database superuser to run MapReduce jobs with GPFDIST input unless the user has the appropriate rights granted.

Description

MapReduce is a programming model developed by Google for processing and generating large data sets on an array of commodity servers. Greenplum MapReduce allows programmers who are familiar with the MapReduce paradigm to write map and reduce functions and submit them to the Greenplum Database parallel engine for processing.

gpmapreduce is the Greenplum MapReduce program. You configure a Greenplum MapReduce job via a YAML-formatted configuration file that you pass to the program for execution by the Greenplum Database parallel engine. The Greenplum Database system distributes the input data, runs the program across a set of machines, handles machine failures, and manages the required inter-machine communication.

Options

-f config.yaml

Required. The YAML file that contains the Greenplum MapReduce job definitions. Refer to gpmapreduce.yaml for the format and content of the parameters that you specify in this file.

-? | –help

Show help, then exit.

-V | –version

Show version information, then exit.

-v | –verbose

Show verbose output.

-x | –explain

Do not run MapReduce jobs, but produce explain plans.

-X | –explain-analyze

Run MapReduce jobs and produce explain-analyze plans.

-k | –keyname=value

Sets a YAML variable. A value is required. Defaults to “key” if no variable name is specified.

Connection Options

-h host | –host host

Specifies the host name of the machine on which the Greenplum master database server is running. If not specified, reads from the environment variable PGHOST or defaults to localhost.

-p port | –port port

Specifies the TCP port on which the Greenplum master database server is listening for connections. If not specified, reads from the environment variable PGPORT or defaults to 5432.

-U username | –username username

The database role name to connect as. If not specified, reads from the environment variable PGUSER or defaults to the current system user name.

-W | –password

Force a password prompt.

Examples

Run a MapReduce job as defined in my_mrjob.yaml and connect to the database mydatabase:

gpmapreduce -f my_mrjob.yaml mydatabase

See Also

gpmapreduce.yaml