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From Apache Wiki <wikidi...@apache.org>
Subject [Hadoop Wiki] Update of "Hbase/DataModel" by DrewRaines
Date Wed, 31 Dec 2008 21:45:40 GMT
Dear Wiki user,

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

The following page has been changed by DrewRaines:
http://wiki.apache.org/hadoop/Hbase/DataModel

The comment on the change is:
Remove apostrophes from possessive its.

------------------------------------------------------------------------------
  [[Anchor(columns)]]
  = Column Families =
  
- A column family regroups data of a same nature in HBase and has no constraint on the type.
The families are part of the table schema and stay the same for each row; what differs from
rows to rows is that the column keys can be very sparse. For example, row "20080702" may have
in it's "info:" family the following column keys:
+ A column family regroups data of a same nature in HBase and has no constraint on the type.
The families are part of the table schema and stay the same for each row; what differs from
rows to rows is that the column keys can be very sparse. For example, row "20080702" may have
in its "info:" family the following column keys:
  ||info:aaa||
  ||info:bbb||
  ||info:ccc||
@@ -46, +46 @@

  [[Anchor(ts)]]
  = Timestamps =
  
- The values in HBase may have multiple versions kept according to the family configuration.
By default, HBase sets the timestamp to each new value to current time in milliseconds and
returns the latest version when a cell is retrieved. The developer can also provide it's own
timestamps when inserting data as he can specify a certain timestamp when fetching it.
+ The values in HBase may have multiple versions kept according to the family configuration.
By default, HBase sets the timestamp to each new value to current time in milliseconds and
returns the latest version when a cell is retrieved. The developer can also provide its own
timestamps when inserting data as he can specify a certain timestamp when fetching it.
  
  [[Anchor(famatt)]]
  = Family Attributes =
@@ -69, +69 @@

  = Real Life Example =
  The following example is the same one given during HBase ETS presentation available in french
in the presentation page.
  
- A good example on how to demonstrate the HBase data model is a blog because of it's simple
features and domain. Suppose the following mini-SRS:
+ A good example on how to demonstrate the HBase data model is a blog because of its simple
features and domain. Suppose the following mini-SRS:
   * The blog entries, which consist of a title, an under title, a date, an author, a type
(or tag), a text, and comments, can be created and updated by logged in users.
   * The users, which consist of a username, a password, and a name, can log in and log out.
   * The comments, which consist of a title, an author, and text, can be written anonymously
by visitors as long as their identity is verified by a captcha.

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