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From lewi...@apache.org
Subject svn commit: r1567709 - /gora/site/trunk/content/current/gora-hbase.md
Date Wed, 12 Feb 2014 18:18:23 GMT
Author: lewismc
Date: Wed Feb 12 18:18:23 2014
New Revision: 1567709

URL: http://svn.apache.org/r1567709
Log:
CMS commit to gora by lewismc

Modified:
    gora/site/trunk/content/current/gora-hbase.md

Modified: gora/site/trunk/content/current/gora-hbase.md
URL: http://svn.apache.org/viewvc/gora/site/trunk/content/current/gora-hbase.md?rev=1567709&r1=1567708&r2=1567709&view=diff
==============================================================================
--- gora/site/trunk/content/current/gora-hbase.md (original)
+++ gora/site/trunk/content/current/gora-hbase.md Wed Feb 12 18:18:23 2014
@@ -32,26 +32,38 @@ Here you can see that we require the def
 
 The table element; where we specify: 
 
-* a parameter relating to the HBase table name e.g. name=<b>"Employee"</b>, 
+1. a parameter relating to the HBase table name e.g. name=<b>"Employee"</b>,

 
-* 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;
+2. 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;
 
-  * <b>name</b>: family name e.g. info
+    <b>name</b>: family name e.g. info
 
     <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>.
 
 The class element where we specify of persistent fields which values should map to. This
contains;
-* a parameter containing the Persistent class name e.g. <b>org.apache.gora.examples.generated.Employee</b>,

-* a parameter containing the keyClass e.g. <b>java.lang.String</b> which specifies
the keys which map to the field values, 
-* a parameter containing the Table name e.g. <b>Employee</b> which matches to
the above Table definition,
-* finally nested child element(s) mapping fields which are to be persisted into HBase. These
fields need to be configured such that they receive;
+
+1. a parameter containing the Persistent class name e.g. <b>org.apache.gora.examples.generated.Employee</b>,

+
+2. a parameter containing the keyClass e.g. <b>java.lang.String</b> which specifies
the keys which map to the field values, 
+
+3. a parameter containing the Table name e.g. <b>Employee</b> which matches to
the above Table definition,
+
+4. finally nested child element(s) mapping fields which are to be persisted into HBase. These
fields need to be configured such that they receive;
 
     a parameter containing the <b>name</b> e.g. (name, dateOfBirth, ssn and salary
respectively), 
+
     a parameter containing the column <b>family</b> to which they belong e.g.
(all info in this case), 
+
     an optional parameter <b>qualifier</b>, which enables more granular control
over the data to be persisted into HBase.



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