Please refer to the README file in hive package: ... Metadata Store --------------
Metadata is in an embedded Derby database whose location is determined by the hive configuration variable named javax.jdo.option.ConnectionURL. By default (see conf/hive-default.xml) - this location is ./metastore_db Right now - in the default configuration, this metadata can only be seen by one user at a time. Metastore can be stored in any database that is supported by JPOX. The location and the type of the RDBMS can be controlled by the two variables 'javax.jdo.option.ConnectionURL' and 'javax.jdo.option.ConnectionDriverName'. Refer to JDO (or JPOX) documentation for more details on supported databases. The database schema is defined in JDO metadata annotations file package.jdo at src/contrib/hive/metastore/src/model. In the future - the metastore itself can be a standalone server. ... Zheng On Mon, Dec 1, 2008 at 10:04 PM, Josh Ferguson <[EMAIL PROTECTED]> wrote: > One more thing, can someone explain to me what metastore_db is and what its > significance is, apparently if I run hive from separate places certain > instances can find some tables and some can't. I'm assuming this > metastore_db is supposed to be shared around, and this it is updated at some > point and maintained somehow? Can someone explain this piece of the > architecture to me? > > Josh > -- Yours, Zheng
