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The following page has been changed by AlanGates:
http://wiki.apache.org/pig/MetadataInterfaceProposal

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  = Proposed Design for Pig Metadata Interface =
- With the introduction of SQL, Pig needs to be able to communicate with 
external metadata services.  These communications will includes such
+ With the introduction of SQL, Pig needs to be able to communicate with 
external metadata services.  These communications will include such
  operations as creating, altering, and dropping databases, tables, etc.  It 
will also include metadata queries, such as requests to show available
  tables, etc.  DDL operations of these sorts will be beyond the scope of the 
proposed metadata
  interfaces for load and storage functions.  However, Pig should not be 
tightly tied to a single metadata implementation.  It should be able to
- work with Owl, Hive's metastore, or any other metadata source that is added 
to Hadoop.  To this end this document proposes an interface for
+ work with Owl, Hive's metastore, or any other metadata source that is added 
to Hadoop.  To this end, this document proposes an interface for
  operating with metadata systems.  Different metadata connectors can then be 
implemented, one for each metadata system.
  
  == Interface ==
- 
  This interface will allow users to find information about tables, databases, 
etc. in the metadata store.  For each call, it will pass the portion
  of the syntax tree relavant to the operation to the metadata connector.  
These structures will be versioned.
  
@@ -39, +38 @@

  configuration file.  It will specify the URI of the server to use and the 
implementation of !MetadataDDL to use with this server.
  
  == Accessing Global Metadata from Pig Latin ==
- Pig Latin will not support a call to metadata within the language itself.  
Instead, it will support the ability to invoke a SQL DDL command.
+ Pig Latin will not support a call to metadata within the language itself.  
Instead, it will support the ability to invoke a Pig SQL DDL command.
  This SQL will then be sent to the SQL parser and dispatched through the 
metadata service as before.
  
  {{{

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