org.hibernate.cfg.JDBCBinderException: org.hibernate.mapping.Column(OWNER) already exist in org.hibernate.mapping.Table(null.OLAPSYS.ALL$OLAP2_DIM_LEVEL_ATTR_MAPS)
at org.hibernate.cfg.JDBCBinder.processBasicColumns(JDBCBinder.java:725)
at org.hibernate.cfg.JDBCBinder.readFromDatabase(JDBCBinder.java:106)
at org.hibernate.cfg.JDBCMetaDataConfiguration.readFromJDBC(JDBCMetaDataConfiguration.java:40)
at org.hibernate.eclipse.console.wizards.ArtifactGeneratorWizard$3.execute(ArtifactGeneratorWizard.java:213)
at org.hibernate.console.ConsoleConfiguration.execute(ConsoleConfiguration.java:76)
at org.hibernate.eclipse.console.wizards.ArtifactGeneratorWizard.buildConfiguration(ArtifactGeneratorWizard.java:210)
at org.hibernate.eclipse.console.wizards.ArtifactGeneratorWizard.doFinish(ArtifactGeneratorWizard.java:147)
at org.hibernate.eclipse.console.wizards.ArtifactGeneratorWizard.access$0(ArtifactGeneratorWizard.java:127)
at org.hibernate.eclipse.console.wizards.ArtifactGeneratorWizard$1.run(ArtifactGeneratorWizard.java:95)
at org.eclipse.jface.operation.ModalContext$ModalContextThread.run(ModalContext.java:105)

I was also getting same error. I was going thru FAQ and found that we need to set hiibernate.default_schema to your schema name. Also check up the DB connection parameters are correct. The problem got resolved after this setting.

The correct parameter should be hibernate.default_schema (I copied and pasted the one with two "i" from the previous response and it took me a while to realize why it wasn't working).