scially/accumulo-examples

Apache Accumulo Examples

Apache Accumulo Examples

Setup instructions

Before running any of the examples, the following steps must be performed.

1. Install and run Accumulo via the instructions found in INSTALL.md of Accumulo's tarball. Remember the instance name. It will be referred to as "instance" throughout the examples. A comma-separated list of zookeeper servers will be referred to as "zookeepers".

2. Create an Accumulo user (for help see the 'User Administration' section of the user manual), or use the root user. This user and their password should replace any reference to "username" or "password" in the examples. This user needs the ability to create tables.

3. Clone and build this repository.

    git clone https://github.com/apache/accumulo-examples.git
    mvn clean package
   

4. Specify Accumulo connection information in conf/accumulo-client.properties. Some old examples still read connection information from an examples.conf file so that should also be configured.

    cd accumulo-examples
    nano conf/accumulo-client.properties
    cp examples.conf.template examples.conf
    nano examples.conf
   

5. The examples have some custom iterators that need to be executed by Accumulo tablet servers. Make them available by copying the accumulo-examples.jar to Accumulo's lib/ext directory.

    cp target/accumulo-examples-X.Y.Z.jar /path/accumulo/lib/ext/
   

6. Each Accumulo example has its own documentation and instructions for running the example which are linked to below.

When running the examples, remember the tips below:

• Examples are run using the runex command which is located in the bin/ directory of this repo. The runex command is a simple wrapper around the Maven Exec plugin.
• Commands intended to be run in bash are prefixed by '$' and should be run from the root of this repository.
• Several examples use the accumulo and accumulo-util commands which are expected to be on your PATH. These commands are found in the bin/ directory of your Accumulo installation.
• Commands intended to be run in the Accumulo shell are prefixed by '>'.

Available Examples

Each example below highlights a feature of Apache Accumulo.

Example	Description
batch	Using the batch writer and batch scanner
bloom	Creating a bloom filter enabled table to increase query performance
bulkIngest	Ingesting bulk data using map/reduce jobs on Hadoop
classpath	Using per-table classpaths
client	Using table operations, reading and writing data in Java.
combiner	Using example StatsCombiner to find min, max, sum, and count.
compactionStrategy	Configuring a compaction strategy
constraints	Using constraints with tables.
dirlist	Storing filesystem information.
export	Exporting and importing tables.
filedata	Storing file data.
filter	Using the AgeOffFilter to remove records more than 30 seconds old.
helloworld	Inserting records both inside map/reduce jobs and outside. And reading records between two rows.
isolation	Using the isolated scanner to ensure partial changes are not seen.
mapred	Using MapReduce to read from and write to Accumulo tables.
maxmutation	Limiting mutation size to avoid running out of memory.
regex	Using MapReduce and Accumulo to find data using regular expressions.
reservations	Using conditional mutations to implement simple reservation system.
rgbalancer	Using a balancer to spread groups of tablets within a table evenly
rowhash	Using MapReduce to read a table and write to a new column in the same table.
sample	Building and using sample data in Accumulo.
shard	Using the intersecting iterator with a term index partitioned by document.
tabletofile	Using MapReduce to read a table and write one of its columns to a file in HDFS.
terasort	Generating random data and sorting it using Accumulo.
visibility	Using visibilities (or combinations of authorizations). Also shows user permissions.

Release Testing

This repository can be used to test Accumulo release candidates. See docs/release-testing.md.