docs/src/main/resources/examples/README.filter - accumulo - Git at Google

 Title: Apache Accumulo Filter Example
 Notice:    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
            .
              http://www.apache.org/licenses/LICENSE-2.0
            .
            Unless required by applicable law or agreed to in writing,
            software distributed under the License is distributed on an
            "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
            KIND, either express or implied.  See the License for the
            specific language governing permissions and limitations
            under the License.

 This is a simple filter example. It uses the AgeOffFilter that is provided as
 part of the core package org.apache.accumulo.core.iterators.user. Filters are
 iterators that select desired key/value pairs (or weed out undesired ones).
 Filters extend the org.apache.accumulo.core.iterators.Filter class
 and must implement a method accept(Key k, Value v). This method returns true
 if the key/value pair are to be delivered and false if they are to be ignored.
 Filter takes a "negate" parameter which defaults to false. If set to true, the
 return value of the accept method is negated, so that key/value pairs accepted
 by the method are omitted by the Filter.

     username@instance> createtable filtertest
     username@instance filtertest> setiter -t filtertest -scan -p 10 -n myfilter -ageoff
     AgeOffFilter removes entries with timestamps more than <ttl> milliseconds old
     ----------> set AgeOffFilter parameter negate, default false keeps k/v that pass accept method, true rejects k/v that pass accept method:
     ----------> set AgeOffFilter parameter ttl, time to live (milliseconds): 30000
     ----------> set AgeOffFilter parameter currentTime, if set, use the given value as the absolute time in milliseconds as the current time of day:
     username@instance filtertest> scan
     username@instance filtertest> insert foo a b c
     username@instance filtertest> scan
     foo a:b []    c
     username@instance filtertest>

 ... wait 30 seconds ...

     username@instance filtertest> scan
     username@instance filtertest>

 Note the absence of the entry inserted more than 30 seconds ago. Since the
 scope was set to "scan", this means the entry is still in Accumulo, but is
 being filtered out at query time. To delete entries from Accumulo based on
 the ages of their timestamps, AgeOffFilters should be set up for the "minc"
 and "majc" scopes, as well.

 To force an ageoff of the persisted data, after setting up the ageoff iterator
 on the "minc" and "majc" scopes you can flush and compact your table. This will
 happen automatically as a background operation on any table that is being
 actively written to, but can also be requested in the shell.

 The first setiter command used the special -ageoff flag to specify the
 AgeOffFilter, but any Filter can be configured by using the -class flag. The
 following commands show how to enable the AgeOffFilter for the minc and majc
 scopes using the -class flag, then flush and compact the table.

     username@instance filtertest> setiter -t filtertest -minc -majc -p 10 -n myfilter -class org.apache.accumulo.core.iterators.user.AgeOffFilter
     AgeOffFilter removes entries with timestamps more than <ttl> milliseconds old
     ----------> set AgeOffFilter parameter negate, default false keeps k/v that pass accept method, true rejects k/v that pass accept method:
     ----------> set AgeOffFilter parameter ttl, time to live (milliseconds): 30000
     ----------> set AgeOffFilter parameter currentTime, if set, use the given value as the absolute time in milliseconds as the current time of day:
     username@instance filtertest> flush
     06 10:42:24,806 [shell.Shell] INFO : Flush of table filtertest initiated...
     username@instance filtertest> compact
     06 10:42:36,781 [shell.Shell] INFO : Compaction of table filtertest started for given range
     username@instance filtertest> flush -t filtertest -w
     06 10:42:52,881 [shell.Shell] INFO : Flush of table filtertest completed.
     username@instance filtertest> compact -t filtertest -w
     06 10:43:00,632 [shell.Shell] INFO : Compacting table ...
     06 10:43:01,307 [shell.Shell] INFO : Compaction of table filtertest completed for given range
     username@instance filtertest>

 By default, flush and compact execute in the background, but with the -w flag
 they will wait to return until the operation has completed. Both are
 demonstrated above, though only one call to each would be necessary. A
 specific table can be specified with -t.

 After the compaction runs, the newly created files will not contain any data
 that should have been aged off, and the Accumulo garbage collector will remove
 the old files.

 To see the iterator settings for a table, use config.

     username@instance filtertest> config -t filtertest -f iterator
     ---------+---------------------------------------------+---------------------------------------------------------------------------
     SCOPE    | NAME                                        | VALUE
     ---------+---------------------------------------------+---------------------------------------------------------------------------
     table    | table.iterator.majc.myfilter .............. | 10,org.apache.accumulo.core.iterators.user.AgeOffFilter
     table    | table.iterator.majc.myfilter.opt.ttl ...... | 30000
     table    | table.iterator.majc.vers .................. | 20,org.apache.accumulo.core.iterators.user.VersioningIterator
     table    | table.iterator.majc.vers.opt.maxVersions .. | 1
     table    | table.iterator.minc.myfilter .............. | 10,org.apache.accumulo.core.iterators.user.AgeOffFilter
     table    | table.iterator.minc.myfilter.opt.ttl ...... | 30000
     table    | table.iterator.minc.vers .................. | 20,org.apache.accumulo.core.iterators.user.VersioningIterator
     table    | table.iterator.minc.vers.opt.maxVersions .. | 1
     table    | table.iterator.scan.myfilter .............. | 10,org.apache.accumulo.core.iterators.user.AgeOffFilter
     table    | table.iterator.scan.myfilter.opt.ttl ...... | 30000
     table    | table.iterator.scan.vers .................. | 20,org.apache.accumulo.core.iterators.user.VersioningIterator
     table    | table.iterator.scan.vers.opt.maxVersions .. | 1
     ---------+---------------------------------------------+---------------------------------------------------------------------------
     username@instance filtertest>

 When setting new iterators, make sure to order their priority numbers
 (specified with -p) in the order you would like the iterators to be applied.
 Also, each iterator must have a unique name and priority within each scope.
	Title: Apache Accumulo Filter Example
	Notice: 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
	.
	http://www.apache.org/licenses/LICENSE-2.0
	.
	Unless required by applicable law or agreed to in writing,
	software distributed under the License is distributed on an
	"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
	KIND, either express or implied. See the License for the
	specific language governing permissions and limitations
	under the License.

	This is a simple filter example. It uses the AgeOffFilter that is provided as
	part of the core package org.apache.accumulo.core.iterators.user. Filters are
	iterators that select desired key/value pairs (or weed out undesired ones).
	Filters extend the org.apache.accumulo.core.iterators.Filter class
	and must implement a method accept(Key k, Value v). This method returns true
	if the key/value pair are to be delivered and false if they are to be ignored.
	Filter takes a "negate" parameter which defaults to false. If set to true, the
	return value of the accept method is negated, so that key/value pairs accepted
	by the method are omitted by the Filter.

	username@instance> createtable filtertest
	username@instance filtertest> setiter -t filtertest -scan -p 10 -n myfilter -ageoff
	AgeOffFilter removes entries with timestamps more than <ttl> milliseconds old
	----------> set AgeOffFilter parameter negate, default false keeps k/v that pass accept method, true rejects k/v that pass accept method:
	----------> set AgeOffFilter parameter ttl, time to live (milliseconds): 30000
	----------> set AgeOffFilter parameter currentTime, if set, use the given value as the absolute time in milliseconds as the current time of day:
	username@instance filtertest> scan
	username@instance filtertest> insert foo a b c
	username@instance filtertest> scan
	foo a:b [] c
	username@instance filtertest>

	... wait 30 seconds ...

	username@instance filtertest> scan
	username@instance filtertest>

	Note the absence of the entry inserted more than 30 seconds ago. Since the
	scope was set to "scan", this means the entry is still in Accumulo, but is
	being filtered out at query time. To delete entries from Accumulo based on
	the ages of their timestamps, AgeOffFilters should be set up for the "minc"
	and "majc" scopes, as well.

	To force an ageoff of the persisted data, after setting up the ageoff iterator
	on the "minc" and "majc" scopes you can flush and compact your table. This will
	happen automatically as a background operation on any table that is being
	actively written to, but can also be requested in the shell.

	The first setiter command used the special -ageoff flag to specify the
	AgeOffFilter, but any Filter can be configured by using the -class flag. The
	following commands show how to enable the AgeOffFilter for the minc and majc
	scopes using the -class flag, then flush and compact the table.

	username@instance filtertest> setiter -t filtertest -minc -majc -p 10 -n myfilter -class org.apache.accumulo.core.iterators.user.AgeOffFilter
	AgeOffFilter removes entries with timestamps more than <ttl> milliseconds old
	----------> set AgeOffFilter parameter negate, default false keeps k/v that pass accept method, true rejects k/v that pass accept method:
	----------> set AgeOffFilter parameter ttl, time to live (milliseconds): 30000
	----------> set AgeOffFilter parameter currentTime, if set, use the given value as the absolute time in milliseconds as the current time of day:
	username@instance filtertest> flush
	06 10:42:24,806 [shell.Shell] INFO : Flush of table filtertest initiated...
	username@instance filtertest> compact
	06 10:42:36,781 [shell.Shell] INFO : Compaction of table filtertest started for given range
	username@instance filtertest> flush -t filtertest -w
	06 10:42:52,881 [shell.Shell] INFO : Flush of table filtertest completed.
	username@instance filtertest> compact -t filtertest -w
	06 10:43:00,632 [shell.Shell] INFO : Compacting table ...
	06 10:43:01,307 [shell.Shell] INFO : Compaction of table filtertest completed for given range
	username@instance filtertest>

	By default, flush and compact execute in the background, but with the -w flag
	they will wait to return until the operation has completed. Both are
	demonstrated above, though only one call to each would be necessary. A
	specific table can be specified with -t.

	After the compaction runs, the newly created files will not contain any data
	that should have been aged off, and the Accumulo garbage collector will remove
	the old files.

	To see the iterator settings for a table, use config.

	username@instance filtertest> config -t filtertest -f iterator
	---------+---------------------------------------------+---------------------------------------------------------------------------
	SCOPE \| NAME \| VALUE
	---------+---------------------------------------------+---------------------------------------------------------------------------
	table \| table.iterator.majc.myfilter .............. \| 10,org.apache.accumulo.core.iterators.user.AgeOffFilter
	table \| table.iterator.majc.myfilter.opt.ttl ...... \| 30000
	table \| table.iterator.majc.vers .................. \| 20,org.apache.accumulo.core.iterators.user.VersioningIterator
	table \| table.iterator.majc.vers.opt.maxVersions .. \| 1
	table \| table.iterator.minc.myfilter .............. \| 10,org.apache.accumulo.core.iterators.user.AgeOffFilter
	table \| table.iterator.minc.myfilter.opt.ttl ...... \| 30000
	table \| table.iterator.minc.vers .................. \| 20,org.apache.accumulo.core.iterators.user.VersioningIterator
	table \| table.iterator.minc.vers.opt.maxVersions .. \| 1
	table \| table.iterator.scan.myfilter .............. \| 10,org.apache.accumulo.core.iterators.user.AgeOffFilter
	table \| table.iterator.scan.myfilter.opt.ttl ...... \| 30000
	table \| table.iterator.scan.vers .................. \| 20,org.apache.accumulo.core.iterators.user.VersioningIterator
	table \| table.iterator.scan.vers.opt.maxVersions .. \| 1
	---------+---------------------------------------------+---------------------------------------------------------------------------
	username@instance filtertest>

	When setting new iterators, make sure to order their priority numbers
	(specified with -p) in the order you would like the iterators to be applied.
	Also, each iterator must have a unique name and priority within each scope.