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Subject [10/11] accumulo git commit: ACCUMULO-4531 Removed combiners.html
Date Tue, 06 Dec 2016 19:14:49 GMT
ACCUMULO-4531 Removed combiners.html

* Most documentation exists in manual but added some missing text


Branch: refs/heads/master
Commit: fc1a68a99c2bdb5225cb1f19ecf9c6371a28c407
Parents: 2741998
Author: Mike Walch <>
Authored: Tue Dec 6 10:36:12 2016 -0500
Committer: Mike Walch <>
Committed: Tue Dec 6 14:04:54 2016 -0500

 .../asciidoc/chapters/table_configuration.txt   |  7 +-
 docs/src/main/resources/combiners.html          | 87 --------------------
 2 files changed, 6 insertions(+), 88 deletions(-)
diff --git a/docs/src/main/asciidoc/chapters/table_configuration.txt b/docs/src/main/asciidoc/chapters/table_configuration.txt
index a3e4dcd..adffd2e 100644
--- a/docs/src/main/asciidoc/chapters/table_configuration.txt
+++ b/docs/src/main/asciidoc/chapters/table_configuration.txt
@@ -120,6 +120,7 @@ To enable bloom filters, enter the following command in the Shell:
 An extensive example of using Bloom Filters can be found at +docs/examples/ .
 === Iterators
 Iterators provide a modular mechanism for adding functionality to be executed by
 TabletServers when scanning or compacting data. This allows users to efficiently
 summarize, filter, and aggregate data. In fact, the built-in features of cell-level
@@ -299,6 +300,10 @@ To see the iterator settings for a table, use:
 ==== Combiners
+Accumulo supports on the fly lazy aggregation of data using Combiners. Aggregation is
+done at compaction and scan time. No lookup is done at insert time, which` greatly
+speeds up ingest.
 Accumulo allows Combiners to be configured on tables and column
 families. When a Combiner is set it is applied across the values
 associated with any keys that share rowID, column family, and column qualifier.
@@ -346,7 +351,7 @@ Additional Combiners can be added by creating a Java class that extends
 +org.apache.accumulo.core.iterators.Combiner+ and adding a jar containing that
 class to Accumulo's lib/ext directory.
-An example of a Combiner can be found at +docs/examples/src/combiner/
+An example of a Combiner can be found at +docs/examples/
 === Block Cache
diff --git a/docs/src/main/resources/combiners.html b/docs/src/main/resources/combiners.html
deleted file mode 100644
index a5e3dc0..0000000
--- a/docs/src/main/resources/combiners.html
+++ /dev/null
@@ -1,87 +0,0 @@
-  Licensed to the Apache Software Foundation (ASF) under one or more
-  contributor license agreements.  See the NOTICE file distributed with
-  this work for additional information regarding copyright ownership.
-  The ASF licenses this file to You under the Apache License, Version 2.0
-  (the "License"); you may not use this file except in compliance with
-  the License.  You may obtain a copy of the License at
-  Unless required by applicable law or agreed to in writing, software
-  distributed under the License is distributed on an "AS IS" BASIS,
-  See the License for the specific language governing permissions and
-  limitations under the License.
-<title>Accumulo Combiners</title>
-<link rel='stylesheet' type='text/css' href='documentation.css' media='screen'/>
-<h1>Apache Accumulo Documentation : Combiners</h1>
-<p>Accumulo supports on the fly lazy aggregation of data using Combiners. Aggregation
is done at compaction and scan time. No lookup is done at insert time, which` greatly speeds
up ingest.
-<p>Combiners are easy to use. You use the setiters command to configure a combiner
for a table. Allowing a Combiner to apply to a whole column family is an interesting twist
that gives the user great flexibility. The example below demonstrates this flexibility.
-Shell - Apache Accumulo Interactive Shell
-- version: 1.5.0
-- instance id: 863fc0d1-3623-4b6c-8c23-7d4fdb1c8a49
-- type 'help' for a list of available commands
-user@instance&gt; createtable perDayCounts
-user@instance perDayCounts&gt; setiter -t perDayCounts -p 10 -scan -minc -majc -n daycount
-class org.apache.accumulo.core.iterators.user.SummingCombiner
-TypedValueCombiner can interpret Values as a variety of number encodings (VLong, Long, or
String) before combining
-----------&gt; set SummingCombiner parameter columns, &lt;col fam&gt;[:&lt;col
qual&gt;]{,&lt;col fam&gt;[:&lt;col qual&gt;]} escape non aplhanum chars
using %&lt;hex&gt;.: day
-----------&gt; set SummingCombiner parameter type, &lt;VARNUM|LONG|STRING&gt;:
-user@instance perDayCounts&gt; insert foo day 20080101 1
-user@instance perDayCounts&gt; insert foo day 20080101 1
-user@instance perDayCounts&gt; insert foo day 20080103 1
-user@instance perDayCounts&gt; insert bar day 20080101 1
-user@instance perDayCounts&gt; insert bar day 20080101 1
-user@instance perDayCounts&gt; scan
-bar day:20080101 []    2
-foo day:20080101 []    2
-foo day:20080103 []    1
-<p>Implementing a new Combiner is a snap. Simply write some Java code that
-extends <code>org.apache.accumulo.core.iterators.Combiner</code>. A good place
-to look for examples is the <code>org.apache.accumulo.core.iterators.user</code>
package. Also look at the example StatsCombiner.
-<p>To deploy a new aggregator, jar it up and put the jar in accumulo/lib/ext. To see
an example look at <a href='examples/README.combiner'>README.combiner</a>
-<p>If you would like to see what iterators a table has you can use the config command
like in the following example.
-user@instance perDayCounts&gt; config -t perDayCounts -f iterator
-SCOPE    | NAME                                        | VALUE
-table    | table.iterator.majc.daycount .............. | 10,org.apache.accumulo.core.iterators.user.SummingCombiner
-table    | table.iterator.majc.daycount.opt.columns .. | day
-table    | table.iterator.majc.daycount.opt.type ..... | STRING
-table    | table.iterator.majc.vers .................. | 20,org.apache.accumulo.core.iterators.VersioningIterator
-table    | table.iterator.majc.vers.opt.maxVersions .. | 1
-table    | table.iterator.minc.daycount .............. | 10,org.apache.accumulo.core.iterators.user.SummingCombiner
-table    | table.iterator.minc.daycount.opt.columns .. | day
-table    | table.iterator.minc.daycount.opt.type ..... | STRING
-table    | table.iterator.minc.vers .................. | 20,org.apache.accumulo.core.iterators.VersioningIterator
-table    | table.iterator.minc.vers.opt.maxVersions .. | 1
-table    | table.iterator.scan.daycount .............. | 10,org.apache.accumulo.core.iterators.user.SummingCombiner
-table    | table.iterator.scan.daycount.opt.columns .. | day
-table    | table.iterator.scan.daycount.opt.type ..... | STRING
-table    | table.iterator.scan.vers .................. | 20,org.apache.accumulo.core.iterators.VersioningIterator
-table    | table.iterator.scan.vers.opt.maxVersions .. | 1

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