Index: src/site/xdoc/acid-semantics.xml =================================================================== --- src/site/xdoc/acid-semantics.xml (revision 1125196) +++ src/site/xdoc/acid-semantics.xml (working copy) @@ -90,7 +90,7 @@
    -
  1. All mutations are atomic within a row. Any put will either wholely succeed or wholely fail.
  2. +
  3. All mutations are atomic within a row. Any put will either wholely succeed or wholely fail.[3]
    1. An operation that returns a "success" code has completely succeeded.
    2. An operation that returns a "failure" code has completely failed.
    3. @@ -170,7 +170,7 @@
      1. When a client receives a "success" response for any mutation, that mutation is immediately visible to both that client and any client with whom it - later communicates through side channels.
      2. + later communicates through side channels. [3]
      3. A row must never exhibit so-called "time-travel" properties. That is to say, if a series of mutations moves a row sequentially through a series of states, any sequence of concurrent reads will return a subsequence of those states.
      4. @@ -189,7 +189,7 @@
      5. All visible data is also durable data. That is to say, a read will never return data that has not been made durable on disk[2]
      6. Any operation that returns a "success" code (eg does not throw an exception) - will be made durable.
      7. + will be made durable.[3]
      8. Any operation that returns a "failure" code will not be made durable (subject to the Atomicity guarantees above)
      9. All reasonable failure scenarios will not affect any of the guarantees of this document.
      10. @@ -205,6 +205,12 @@
+
+

+ For more information, see the client architecture or data model sections in the HBase book. +

+
+

[1] A consistent view is not guaranteed intra-row scanning -- i.e. fetching a portion of a row in one RPC then going back to fetch another portion of the row in a subsequent RPC. @@ -216,6 +222,10 @@ log. This does not actually imply an fsync() to magnetic media, but rather just that the data has been written to the OS cache on all replicas of the log. In the case of a full datacenter power loss, it is possible that the edits are not truly durable.

+

[3] Puts will either wholely succeed or wholely fail, provided that they are actually sent + to the RegionServer. If the writebuffer is used, Puts will not be sent until the writebuffer is filled + or it is explicitly flushed.

+