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Posted to commits@hbase.apache.org by mi...@apache.org on 2014/10/07 06:05:29 UTC
git commit: HBASE-9005 Improve documentation around
KEEP_DELETED_CELLS, time range scans, and delete markers
Repository: hbase
Updated Branches:
refs/heads/master b9701d056 -> baaaac020
HBASE-9005 Improve documentation around KEEP_DELETED_CELLS, time range scans, and delete markers
Project: http://git-wip-us.apache.org/repos/asf/hbase/repo
Commit: http://git-wip-us.apache.org/repos/asf/hbase/commit/baaaac02
Tree: http://git-wip-us.apache.org/repos/asf/hbase/tree/baaaac02
Diff: http://git-wip-us.apache.org/repos/asf/hbase/diff/baaaac02
Branch: refs/heads/master
Commit: baaaac020296e1587dd3b5f902caacdd612cfd88
Parents: b9701d0
Author: Misty Stanley-Jones <ms...@cloudera.com>
Authored: Thu Oct 2 09:21:58 2014 +1000
Committer: Misty Stanley-Jones <ms...@cloudera.com>
Committed: Tue Oct 7 14:05:13 2014 +1000
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src/main/docbkx/schema_design.xml | 30 ++++++++++++++++++++++--------
1 file changed, 22 insertions(+), 8 deletions(-)
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http://git-wip-us.apache.org/repos/asf/hbase/blob/baaaac02/src/main/docbkx/schema_design.xml
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diff --git a/src/main/docbkx/schema_design.xml b/src/main/docbkx/schema_design.xml
index 40afefc..65e64b0 100644
--- a/src/main/docbkx/schema_design.xml
+++ b/src/main/docbkx/schema_design.xml
@@ -513,20 +513,34 @@ public static byte[][] getHexSplits(String startKey, String endKey, int numRegio
<section
xml:id="cf.keep.deleted">
<title> Keeping Deleted Cells </title>
- <para>ColumnFamilies can optionally keep deleted cells. That means deleted cells can still be
- retrieved with <link
+ <para>By default, delete markers extend back to the beginning of time. Therefore, <link
xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/Get.html">Get</link>
or <link
xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/Scan.html">Scan</link>
- operations, as long these operations have a time range specified that ends before the
- timestamp of any delete that would affect the cells. This allows for point in time queries
- even in the presence of deletes. </para>
+ operations will not see a deleted cell (row or column), even when the Get or Scan operation
+ indicates a time range
+ before the delete marker was placed.</para>
+ <para>ColumnFamilies can optionally keep deleted cells. In this case, deleted cells can still be
+ retrieved, as long as these operations specify a time range that ends before the timestamp of
+ any delete that would affect the cells. This allows for point-in-time queries even in the
+ presence of deletes. </para>
<para> Deleted cells are still subject to TTL and there will never be more than "maximum number
of versions" deleted cells. A new "raw" scan options returns all deleted rows and the delete
markers. </para>
- <para>See <link
- xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/HColumnDescriptor.html">HColumnDescriptor</link>
- for more information. </para>
+ <example>
+ <title>Change the Value of <code>KEEP_DELETED_CELLS</code> Using HBase Shell</title>
+ <screen>hbase> hbase> alter ‘t1′, NAME => ‘f1′, KEEP_DELETED_CELLS => true</screen>
+ </example>
+ <example>
+ <title>Change the Value of <code>KEEP_DELETED_CELLS</code> Using the API</title>
+ <programlisting language="java">...
+HColumnDescriptor.setKeepDeletedCells(true);
+...
+ </programlisting>
+ </example>
+ <para>See the API documentation for <link
+ xlink:href="http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/HColumnDescriptor.html#KEEP_DELETED_CELLS"
+ >KEEP_DELETED_CELLS</link> for more information. </para>
</section>
<section
xml:id="secondary.indexes">