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From Apache Wiki <wikidi...@apache.org>
Subject [Lucene-hadoop Wiki] Update of "HbaseShell/HQL" by InchulSong
Date Tue, 07 Aug 2007 13:20:18 GMT
Dear Wiki user,

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The following page has been changed by InchulSong:
http://wiki.apache.org/lucene-hadoop/HbaseShell/HQL

The comment on the change is:
some refinements on syntax

------------------------------------------------------------------------------
  
  We borrowed the syntax definition style from MySQL.
  
-  ''-- See [:HbaseShell/Examples], fill it with this page!! ^^ [[BR]]udanax''
+  ''-- See [:HBaseShell/Examples], fill it with this page!! ^^ [[BR]]udanax''
  
  == Data Definition Statements ==
  
@@ -57, +57 @@

  }}}
  
  == Data Manipulation Statements ==
- === START TRANSACTION, COMMIT, and ROLLBACK Syntax ===
- You can group togather a sequence of data manipulation statements in a single-row transaction.
- 
- {{{
- START TRANSACTION table_name ON 'row-key' | BEGIN table_name ON 'row-key'
- COMMIT 
- ROLLBACK 
- }}}
- 
- The START TRANSACTION and BEGIN statements begin a new single-row transaction. 
- COMMIT commits the current transaction, making its changes permanent. 
- ROLLBACK rolls back the current transaction, canceling its changes. 
- 
- By default, for every statement execution that updates a table, 
- Hbase stores the update on disk.
- 
  === SELECT Syntax ===
  SELECT enables you to retrieve a subset of data in a table.
  
  {{{
  SELECT { column_name [, column_name] ... | * }
    FROM table_name
-   [WHERE cond_expr [AND cond_expr] ...]
+   [WHERE row = 'row-key']
    [VERSION_LIMIT {n | all}] [LIMIT n]
  
  column_name: 
      column_family_name:column_label_name
    | column_family_name:
- 
- cond_expr:
-     { row | column_name | timestamp } op 'value'
- 
- op:
-   = | < | > | <= | >= 
  }}}
  
  You should quote column_name with single quotes if column_name has spaces in it.
  
- If only column_family_name part is specified for a column, the values from all the column_label_names
in the column_family_name are retrieved.
+ If you specify only column_family_name part for a column, you get values from all the column_label_names
in the column_family_name.
  
- VERSION_LIMIT retrieves only the last n versions of values in a cell. If neither VER_LIMIT
nor any condition on tiemstamp is specified, only the latest version of value in a cell is
returned. 
+ VERSION_LIMIT retrieves only the last n versions of values in a cell. 
+ If you do not specify VERSION_LIMIT, you get only the latest version of value in a cell.

  
  LIMIT returns only the last n rows in row-key order.
  
@@ -107, +86 @@

  {{{
  INSERT INTO table_name (colmn_name [, column_name] ...)
    VALUES ('value' [, 'value'] ...)
-   [WHERE cond_expr [AND cond_expr] ...]
+   [WHERE row = 'row-key']
    [WITH TIMESTAMP 'value']
  }}}
  
@@ -121, +100 @@

  {{{
  DELETE { column_name, [, column_name] ... | * }
    FROM table_name
-   [WHERE cond_expr [AND cond_expr] ...]
+   [WHERE row = 'row-key']
  }}}
  
+ === START TRANSACTION, COMMIT, and ROLLBACK Syntax ===
+ You can group togather a sequence of data manipulation statements in a single-row transaction.
+ 
+ {{{
+ START TRANSACTION ON 'row-key' OF table_name | BEGIN ON 'row-key' OF table_name
+ COMMIT 
+ ROLLBACK 
+ }}}
+ 
+ The START TRANSACTION and BEGIN statements begin a new single-row transaction. 
+ COMMIT commits the current transaction, making its changes permanent. 
+ ROLLBACK rolls back the current transaction, canceling its changes. 
+ 
+ By default, for every statement execution that updates a table, 
+ Hbase stores the update on disk.
+ 

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