HBASE-4504 book.xml - filters
git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1176943 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Doug Meil
parent
2c988abf35
commit
1bc1b593f9
|
|
@ -1234,11 +1234,6 @@ HTable table2 = new HTable(conf2, "myTable");</programlisting>
|
||||||
<para>For fine-grained control of batching of
|
<para>For fine-grained control of batching of
|
||||||
<classname>Put</classname>s or <classname>Delete</classname>s,
|
<classname>Put</classname>s or <classname>Delete</classname>s,
|
||||||
see the <link xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/HTable.html#batch%28java.util.List%29">batch</link> methods on HTable.
|
see the <link xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/HTable.html#batch%28java.util.List%29">batch</link> methods on HTable.
|
||||||
</para>
|
|
||||||
</section>
|
|
||||||
<section xml:id="client.filter"><title>Filters</title>
|
|
||||||
<para><link xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/Get.html">Get</link> and <link xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/Scan.html">Scan</link> instances can be
|
|
||||||
optionally configured with <link xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/Filter.html">filters</link> which are applied on the RegionServer.
|
|
||||||
</para>
|
</para>
|
||||||
</section>
|
</section>
|
||||||
<section xml:id="client.external"><title>External Clients</title>
|
<section xml:id="client.external"><title>External Clients</title>
|
||||||
|
|
@ -1247,6 +1242,134 @@ HTable table2 = new HTable(conf2, "myTable");</programlisting>
|
||||||
</section>
|
</section>
|
||||||
</section>
|
</section>
|
||||||
|
|
||||||
|
<section xml:id="client.filter"><title>Client Filters</title>
|
||||||
|
<para><link xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/Get.html">Get</link> and <link xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/Scan.html">Scan</link> instances can be
|
||||||
|
optionally configured with <link xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/Filter.html">filters</link> which are applied on the RegionServer.
|
||||||
|
</para>
|
||||||
|
<para>Filters can be confusing because there are many different types, and it is best to approach them by understanding the groups
|
||||||
|
of Filter functionality.
|
||||||
|
</para>
|
||||||
|
<section xml:id="client.filter.structural"><title>Structural</title>
|
||||||
|
<para>Structural Filters contain other Filters.</para>
|
||||||
|
<section xml:id="client.filter.structural.fl"><title>FilterList</title>
|
||||||
|
<para><link xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/FilterList.html">FilterList</link>
|
||||||
|
represents a list of Filters with a relationship of <code>FilterList.Operator.MUST_PASS_ALL</code> or
|
||||||
|
<code>FilterList.Operator.MUST_PASS_ONE</code> between the Filters. The following example shows an 'or' between two
|
||||||
|
Filters (checking for either 'my value' or 'my other value' on the same attribute).
|
||||||
|
<programlisting>
|
||||||
|
FilterList list = new FilterList(FilterList.Operator.MUST_PASS_ONE);
|
||||||
|
SingleColumnValueFilter filter1 = new SingleColumnValueFilter(
|
||||||
|
cf,
|
||||||
|
column,
|
||||||
|
CompareOp.EQUAL,
|
||||||
|
Bytes.toBytes("my value")
|
||||||
|
);
|
||||||
|
list.add(filter1);
|
||||||
|
SingleColumnValueFilter filter2 = new SingleColumnValueFilter(
|
||||||
|
cf,
|
||||||
|
column,
|
||||||
|
CompareOp.EQUAL,
|
||||||
|
Bytes.toBytes("my other value")
|
||||||
|
);
|
||||||
|
list.add(filter2);
|
||||||
|
scan.setFilter(list);
|
||||||
|
</programlisting>
|
||||||
|
</para>
|
||||||
|
</section>
|
||||||
|
</section>
|
||||||
|
<section xml:id="client.filter.cv"><title>Column Value</title>
|
||||||
|
<section xml:id="client.filter.cv.scvf"><title>SingleColumnValueFilter</title>
|
||||||
|
<para><link xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/SingleColumnValueFilter.html">SingleColumnValueFilter</link>
|
||||||
|
can be used to test column values for equivalence (<code><link xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/CompareFilter.CompareOp.html">CompareOp.EQUAL</link>
|
||||||
|
</code>), inequality (<code>CompareOp.NOT_EQUAL</code>), or ranges
|
||||||
|
(e.g., <code>CompareOp.GREATER</code>). The folowing is example of testing equivalence a column to a String value "my value"...
|
||||||
|
<programlisting>
|
||||||
|
SingleColumnValueFilter filter = new SingleColumnValueFilter(
|
||||||
|
cf,
|
||||||
|
column,
|
||||||
|
CompareOp.EQUAL,
|
||||||
|
Bytes.toBytes("my value")
|
||||||
|
);
|
||||||
|
scan.setFilter(filter);
|
||||||
|
</programlisting>
|
||||||
|
</para>
|
||||||
|
</section>
|
||||||
|
</section>
|
||||||
|
<section xml:id="client.filter.cvp"><title>Column Value Comparators</title>
|
||||||
|
<para>There are several Comparator classes in the Filter package that deserve special mention.
|
||||||
|
These Comparators are used in concert with other Filters, such as <xref linkend="client.filter.cv.scvf" />.
|
||||||
|
</para>
|
||||||
|
<section xml:id="client.filter.cvp.rcs"><title>RegexStringComparator</title>
|
||||||
|
<para><link xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/RegexStringComparator.html">RegexStringComparator</link>
|
||||||
|
supports regular expressions for value comparisons.
|
||||||
|
<programlisting>
|
||||||
|
RegexStringComparator comp = new RegexStringComparator("my."); // any value that starts with 'my'
|
||||||
|
SingleColumnValueFilter filter = new SingleColumnValueFilter(
|
||||||
|
cf,
|
||||||
|
column,
|
||||||
|
CompareOp.EQUAL,
|
||||||
|
comp
|
||||||
|
);
|
||||||
|
scan.setFilter(filter);
|
||||||
|
</programlisting>
|
||||||
|
See the Oracle JavaDoc for <link xlink:href="http://download.oracle.com/javase/6/docs/api/java/util/regex/Pattern.html">supported RegEx patterns in Java</link>.
|
||||||
|
</para>
|
||||||
|
</section>
|
||||||
|
<section xml:id="client.filter.cvp.rcs"><title>SubstringComparator</title>
|
||||||
|
<para><link xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/SubstringComparator.html">SubstringComparator</link>
|
||||||
|
can be used to determine if a given substring exists in a value. The comparison is case-insensitive.
|
||||||
|
</para>
|
||||||
|
<programlisting>
|
||||||
|
SubstringComparator comp = new SubstringComparator("y val"); // looking for 'my value'
|
||||||
|
SingleColumnValueFilter filter = new SingleColumnValueFilter(
|
||||||
|
cf,
|
||||||
|
column,
|
||||||
|
CompareOp.EQUAL,
|
||||||
|
comp
|
||||||
|
);
|
||||||
|
scan.setFilter(filter);
|
||||||
|
</programlisting>
|
||||||
|
</section>
|
||||||
|
<section xml:id="client.filter.cvp.bfp"><title>BinaryPrefixComparator</title>
|
||||||
|
<para>See <link xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/BinaryPrefixComparator.html">BinaryPrefixComparator</link>.</para>
|
||||||
|
</section>
|
||||||
|
<section xml:id="client.filter.cvp.bc"><title>BinaryComparator</title>
|
||||||
|
<para>See <link xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/BinaryComparator.html">BinaryComparator</link>.</para>
|
||||||
|
</section>
|
||||||
|
</section>
|
||||||
|
<section xml:id="client.filter.kvm"><title>KeyValue Metadata</title>
|
||||||
|
<para>As HBase stores data internally as KeyValue pairs, KeyValue Metadata Filters evaluate the existence of keys (i.e., ColumnFamily:Column qualifiers)
|
||||||
|
for a row, as opposed to values the previous section.
|
||||||
|
</para>
|
||||||
|
<section xml:id="client.filter.kvm.ff"><title>FamilyFilter</title>
|
||||||
|
<para><link xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/FamilyFilter.html">FamilyFilter</link> can be used
|
||||||
|
to filter on the ColumnFamily. It is generally a better idea to select ColumnFamilies in the Scan than to do it with a Filter.</para>
|
||||||
|
</section>
|
||||||
|
<section xml:id="client.filter.kvm.qf"><title>QualifierFilter</title>
|
||||||
|
<para><link xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/QualifierFilter.html">QualifierFilter</link> can be used
|
||||||
|
to filter based on Column (aka Qualifier) name.
|
||||||
|
</para>
|
||||||
|
</section>
|
||||||
|
<section xml:id="client.filter.kvm.cpf"><title>ColumnPrefixFilter</title>
|
||||||
|
<para><link xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/ColumnPrefixFilter.html">ColumnPrefixFilter</link> can be used
|
||||||
|
to filter based on the lead portion of Column (aka Qualifier) names.
|
||||||
|
</para>
|
||||||
|
</section>
|
||||||
|
</section>
|
||||||
|
<section xml:id="client.filter.row"><title>RowKey</title>
|
||||||
|
<section xml:id="client.filter.row.rf"><title>RowFilter</title>
|
||||||
|
<para>It is generally a better idea to use the startRow/stopRow methods on Scan for row selection, however
|
||||||
|
<link xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/RowFilter.html">RowFilter</link> can also be used.</para>
|
||||||
|
</section>
|
||||||
|
</section>
|
||||||
|
<section xml:id="client.filter.utility"><title>Utility</title>
|
||||||
|
<section xml:id="client.filter.utility.fkof"><title>FirstKeyOnlyFilter</title>
|
||||||
|
<para>This is primarily used for rowcount jobs.
|
||||||
|
See <link xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/FirstKeyOnlyFilter.html">FirstKeyOnlyFilter</link>.</para>
|
||||||
|
</section>
|
||||||
|
</section>
|
||||||
|
</section> <!-- client.filter -->
|
||||||
|
|
||||||
<section xml:id="master"><title>Master</title>
|
<section xml:id="master"><title>Master</title>
|
||||||
<para><code>HMaster</code> is the implementation of the Master Server. The Master server
|
<para><code>HMaster</code> is the implementation of the Master Server. The Master server
|
||||||
is responsible for monitoring all RegionServer instances in the cluster, and is
|
is responsible for monitoring all RegionServer instances in the cluster, and is
|
||||||
|
|
|
||||||
Loading…
Reference in New Issue