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(mysql.info.gz) FEDERATED limitations

Info Catalog (mysql.info.gz) FEDERATED use (mysql.info.gz) FEDERATED storage engine
 
 14.6.4 Limitations of the `FEDERATED' Storage Engine
 ----------------------------------------------------
 
 What the `FEDERATED' storage engine does and doesn't support:
 
    * In the first version, the remote server must be a MySQL server.
      Support by `FEDERATED' for other database engines may be be added
      in the future.
 
    * The remote table that a `FEDERATED' table points to _must_ exist
      before you try to access the table through the `FEDERATED' table.
 
    * It is possible for one `FEDERATED' table to point to another, but
      you must be careful not to create a loop.  You know and have heard
      the screeching of audio feedback? You know what you see visually
      when you place two mirrors in front of each other, how the
      reflection continues for eternity? Well, need we say more?!
 
    * There is no support for transactions.
 
    * There is no way for the `FEDERATED' engine to know if the remote
      table has changed. The reason for this is that this table has to
      work like a data file that would never be written to by anything
      other than the database. The integrity of the data in the local
      table could be breached if there was any change to the remote
      database.
 
    * The `FEDERATED' storage engine supports `SELECT', `INSERT',
      `UPDATE', `DELETE', and indexes.  It does not support `ALTER
      TABLE', `DROP TABLE', or any other Data Definition Language
      statements.  The first implementation does not use Prepared
      statements.  It remains to be seen whether the limited subset of
      the client API for the server supports this capability.
 
    * The implementation uses `SELECT', `INSERT', `UPDATE', `DELETE' and
      not `HANDLER'.
 
    * `FEDERATED' tables do not work with the query cache.
 
 
 Some of these limitations may be lifted in future versions of the
 `FEDERATED' handler.
 
Info Catalog (mysql.info.gz) FEDERATED use (mysql.info.gz) FEDERATED storage engine
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