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From build...@apache.org
Subject svn commit: r897653 - in /websites/staging/gora/trunk/content: ./ current/gora-hbase.html
Date Wed, 12 Feb 2014 18:15:28 GMT
Author: buildbot
Date: Wed Feb 12 18:15:28 2014
New Revision: 897653

Log:
Staging update by buildbot for gora

Modified:
    websites/staging/gora/trunk/content/   (props changed)
    websites/staging/gora/trunk/content/current/gora-hbase.html

Propchange: websites/staging/gora/trunk/content/
------------------------------------------------------------------------------
--- cms:source-revision (original)
+++ cms:source-revision Wed Feb 12 18:15:28 2014
@@ -1 +1 @@
-1567707
+1567708

Modified: websites/staging/gora/trunk/content/current/gora-hbase.html
==============================================================================
--- websites/staging/gora/trunk/content/current/gora-hbase.html (original)
+++ websites/staging/gora/trunk/content/current/gora-hbase.html Wed Feb 12 18:15:28 2014
@@ -160,20 +160,25 @@ module enables <a href="http://hbase.apa
 
 <p>Here you can see that we require the definition of two child elements within the

 <code>gora-orm</code> mapping configuration, namely;</p>
-<p>The table element; where we specify: 
-<em> a parameter relating to the HBase table name e.g. name=<b>"Employee"</b>,

-</em> a nested element containing the type and definition of families we wish to create
within HBase. In this case we create one family <b>info</b> which could have a
combination of any of the following parameters;</p>
-<div class="codehilite"><pre><span class="nt">&lt;b&gt;</span>name<span
class="nt">&lt;/b&gt;</span>: family name e.g. info
-<span class="nt">&lt;b&gt;</span>compression<span class="nt">&lt;/b&gt;</span>:
the compression option to use in HBase. Please see <span class="nt">&lt;a</span>
<span class="na">href=</span><span class="s">&quot;http://hbase.apache.org/book/compression.html&quot;</span><span
class="nt">&gt;</span>HBase documentation<span class="nt">&lt;/a&gt;</span>.
-<span class="nt">&lt;b&gt;</span>blockCache<span class="nt">&lt;/b&gt;</span>:
 an LRU cache that contains three levels of block priority to allow for scan-resistance and
in-memory ColumnFamilies. Please see <span class="nt">&lt;a</span> <span
class="na">href=</span><span class="s">&quot;https://hbase.apache.org/book/regionserver.arch.html#block.cache&quot;</span><span
class="nt">&gt;</span>HBase documentation<span class="nt">&lt;/a&gt;</span>.
-<span class="nt">&lt;b&gt;</span>blockSize<span class="nt">&lt;/b&gt;</span>:
The blocksize can be configured for each ColumnFamily in a table, and this defaults to 64k.
Larger cell values require larger blocksizes. There is an inverse relationship between blocksize
and the resulting StoreFile indexes (i.e., if the blocksize is doubled then the resulting
indexes should be roughly halved). Please see <span class="nt">&lt;a</span>
<span class="na">href=</span><span class="s">&quot;http://hbase.apache.org/book/perf.schema.html#schema.cf.blocksize&quot;</span><span
class="nt">&gt;</span>HBase documentation<span class="nt">&lt;/a&gt;</span>.

-<span class="nt">&lt;b&gt;</span>bloomFilter<span class="nt">&lt;/b&gt;</span>:
Bloom Filters can be enabled per-ColumnFamily. We use <span class="nt">&lt;code&gt;</span>HColumnDescriptor.setBloomFilterType(NONE
| ROW | ROWCOL)<span class="nt">&lt;/code&gt;</span> to enable blooms
per Column Family. Default = NONE for no bloom filters. If ROW, the hash of the row will be
added to the bloom on each insert. If ROWCOL, the hash of the row + column family name + column
family qualifier will be added to the bloom on each key insert. Please see <span class="nt">&lt;a</span>
<span class="na">href=</span><span class="s">&quot;http://hbase.apache.org/book/perf.schema.html#schema.bloom&quot;</span><span
class="nt">&gt;</span>HBase documentation<span class="nt">&lt;/a&gt;</span>.
-<span class="nt">&lt;b&gt;</span>maxVersions<span class="nt">&lt;/b&gt;</span>:
The maximum number of row versions to store is configured per column family via <span class="nt">&lt;code&gt;</span>HColumnDescriptor<span
class="nt">&lt;/code&gt;</span>. The default for max versions is <span
class="nt">&lt;b&gt;</span>3<span class="nt">&lt;/b&gt;</span>.
This is an important parameter because HBase does not overwrite row values, but rather stores
different values per row by time (and qualifier). Excess versions are removed during major
compaction&#39;s. The number of max versions may need to be increased or decreased depending
on application needs. Please see <span class="nt">&lt;a</span> <span class="na">href=</span><span
class="s">&quot;http://hbase.apache.org/book/schema.versions.html&quot;</span><span
class="nt">&gt;</span>HBase documentation<span class="nt">&lt;/a&gt;</span>.
-<span class="nt">&lt;b&gt;</span>timeToLive<span class="nt">&lt;/b&gt;</span>:
ColumnFamilies can set a TTL length in seconds, and HBase will automatically delete rows once
the expiration time is reached. This applies to all versions of a row - even the current one.
The TTL time encoded in the HBase for the row is specified in UTC. Please see <span class="nt">&lt;a</span>
<span class="na">href=</span><span class="s">&quot;https://hbase.apache.org/book/ttl.html&quot;</span><span
class="nt">&gt;</span>HBase documentation<span class="nt">&lt;/a&gt;</span>.
-<span class="nt">&lt;b&gt;</span>inMemory<span class="nt">&lt;/b&gt;</span>:
ColumnFamilies can optionally be defined as in-memory. Data is still persisted to disk, just
like any other ColumnFamily. In-memory blocks have the highest priority in the Block Cache,
but it is not a guarantee that the entire table will be in memory. Please see <span class="nt">&lt;a</span>
<span class="na">href=</span><span class="s">&quot;http://hbase.apache.org/book/perf.schema.html#cf.in.memory&quot;</span><span
class="nt">&gt;</span>HBase documentation<span class="nt">&lt;/a&gt;</span>.
-</pre></div>
-
-
+<p>The table element; where we specify: </p>
+<ul>
+<li>
+<p>a parameter relating to the HBase table name e.g. name=<b>"Employee"</b>,
</p>
+</li>
+<li>
+<p>a nested element containing the type and definition of families we wish to create
within HBase. In this case we create one family <b>info</b> which could have a
combination of any of the following parameters;</p>
+</li>
+<li>
+<p><b>name</b>: family name e.g. info</p>
+<p><b>compression</b>: the compression option to use in HBase. Please see
<a href="http://hbase.apache.org/book/compression.html">HBase documentation</a>.
+<b>blockCache</b>:  an LRU cache that contains three levels of block priority
to allow for scan-resistance and in-memory ColumnFamilies. Please see <a href="https://hbase.apache.org/book/regionserver.arch.html#block.cache">HBase
documentation</a>.
+<b>blockSize</b>: The blocksize can be configured for each ColumnFamily in a
table, and this defaults to 64k. Larger cell values require larger blocksizes. There is an
inverse relationship between blocksize and the resulting StoreFile indexes (i.e., if the blocksize
is doubled then the resulting indexes should be roughly halved). Please see <a href="http://hbase.apache.org/book/perf.schema.html#schema.cf.blocksize">HBase
documentation</a>. 
+<b>bloomFilter</b>: Bloom Filters can be enabled per-ColumnFamily. We use <code>HColumnDescriptor.setBloomFilterType(NONE
| ROW | ROWCOL)</code> to enable blooms per Column Family. Default = NONE for no bloom
filters. If ROW, the hash of the row will be added to the bloom on each insert. If ROWCOL,
the hash of the row + column family name + column family qualifier will be added to the bloom
on each key insert. Please see <a href="http://hbase.apache.org/book/perf.schema.html#schema.bloom">HBase
documentation</a>.
+<b>maxVersions</b>: The maximum number of row versions to store is configured
per column family via <code>HColumnDescriptor</code>. The default for max versions
is <b>3</b>. This is an important parameter because HBase does not overwrite row
values, but rather stores different values per row by time (and qualifier). Excess versions
are removed during major compaction's. The number of max versions may need to be increased
or decreased depending on application needs. Please see <a href="http://hbase.apache.org/book/schema.versions.html">HBase
documentation</a>.
+<b>timeToLive</b>: ColumnFamilies can set a TTL length in seconds, and HBase
will automatically delete rows once the expiration time is reached. This applies to all versions
of a row - even the current one. The TTL time encoded in the HBase for the row is specified
in UTC. Please see <a href="https://hbase.apache.org/book/ttl.html">HBase documentation</a>.
+<b>inMemory</b>: ColumnFamilies can optionally be defined as in-memory. Data
is still persisted to disk, just like any other ColumnFamily. In-memory blocks have the highest
priority in the Block Cache, but it is not a guarantee that the entire table will be in memory.
Please see <a href="http://hbase.apache.org/book/perf.schema.html#cf.in.memory">HBase
documentation</a>.</p>
+</li>
+</ul>
 <p>The class element where we specify of persistent fields which values should map
to. This contains;
 <em> a parameter containing the Persistent class name e.g. <b>org.apache.gora.examples.generated.Employee</b>,

 </em> a parameter containing the keyClass e.g. <b>java.lang.String</b>
which specifies the keys which map to the field values, 



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