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From Apache Wiki <wikidi...@apache.org>
Subject [Lucene-hadoop Wiki] Trivial Update of "Hbase/HbaseShell/ShellPlans" by udanax
Date Thu, 11 Oct 2007 03:17:29 GMT
Dear Wiki user,

You have subscribed to a wiki page or wiki category on "Lucene-hadoop Wiki" for change notification.

The following page has been changed by udanax:
http://wiki.apache.org/lucene-hadoop/Hbase/HbaseShell/ShellPlans

------------------------------------------------------------------------------
  select column_qualifier1, column_qualifier2 from 2d_table(table_name, columnfamily_name)
where row='row key';
  }}}
  
+ 
+ Start Transaction, Commit, and Rollback Syntax 
+ 
+ {{{
+ START TRANSACTION ON 'row-key' OF table_name | BEGIN ON 'row-key' OF table_name
+ COMMIT ['timestamp']
+ ROLLBACK 
+ }}}
+ 
+ You can group together a sequence of data manipulation statements in a single-row transaction.
+ 
+ The START TRANSACTION and BEGIN statements begin a new single-row transaction under the
specified 'row-key' of table_name. 
+ 
+ COMMIT commits the current transaction, making its changes permanent. If timestamp is specified
on commit, all the modifications under the single-row transaction are stored with the specified
timestamp. If not, they are stored with the current time as their timestamps.
+ 
+ ROLLBACK rolls back the current transaction, canceling its changes. 
+ 
+ By default, for every statement execution that updates a table, Hbase immediately stores
the update on disk.
+ 
+ ''~- TRANSACTION on a row-level only -- and this is all you could guarantee in HBase --
may be a bit-over-the-top and require more effort than its worth.  How about implementing
this one last, if it is needed at all? -- St.Ack-~''
  
  
  User Defined Function (UDF)

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