Mirror of Apache Accumulo Examples
Java Shell

README.md

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. All examples read connection information from a properties file. Copy the template and edit it.

    cd accumulo-examples
    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.