svn commit: r1232524 - /hbase/trunk/src/docbkx/book.xml

[dm...@apache.org]

Author: dmeil
Date: Tue Jan 17 18:29:00 2012
New Revision: 1232524

URL: http://svn.apache.org/viewvc?rev=1232524&view=rev
Log:
hbase-5216 book.xml - added detail on Arch "when to use hbase" section

Modified:
    hbase/trunk/src/docbkx/book.xml

Modified: hbase/trunk/src/docbkx/book.xml
URL: http://svn.apache.org/viewvc/hbase/trunk/src/docbkx/book.xml?rev=1232524&r1=1232523&r2=1232524&view=diff
==============================================================================
--- hbase/trunk/src/docbkx/book.xml (original)
+++ hbase/trunk/src/docbkx/book.xml Tue Jan 17 18:29:00 2012
@@ -1251,13 +1251,18 @@ if (!b) {
 	
 	  <section xml:id="arch.overview.when">
 	    <title>When Should I Use HBase?</title>
-	          <para>First, make sure you have enough data.  HBase isn't suitable for every problem.  If you have 
-                hundreds of millions or billions of rows, then HBase is a good candidate.  If you only have a few 
-                thousand/million rows, then using a traditional RDBMS might be a better choice due to the 
-                fact that all of your data might wind up on a single node (or two) and the rest of the cluster may
-                be sitting idle.
+	    	  <para>HBase isn't suitable for every problem.</para>
+	          <para>First, make sure you have enough data.  If you have hundreds of millions or billions of rows, then 
+	            HBase is a good candidate.  If you only have a few thousand/million rows, then using a traditional RDBMS
+	            might be a better choice due to the fact that all of your data might wind up on a single node (or two) and
+	            the rest of the cluster may be sitting idle.
 	          </para>
-	          <para>Second, make sure you have enough hardware.  Even HDFS doesn't do well with anything less than
+	          <para>Second, make sure you can live without all the extra features that an RDBMS provides (e.g., typed columns,
+	          secondary indexes, transactions, advanced query languages, etc.)  An application built against an RDBMS cannot be
+	          "ported" to HBase by simply changing a JDBC driver, for example.  Consider moving from an RDBMS to HBase as a
+	          complete redesign as opposed to a port.	          
+              </para>
+	          <para>Third, make sure you have enough hardware.  Even HDFS doesn't do well with anything less than
                 5 DataNodes (due to things such as HDFS block replication which has a default of 3), plus a NameNode.
                 </para>
                 <para>HBase can run quite well stand-alone on a laptop - but this should be considered a development