Delayed Session Factory for Oracle

DataSource.groovy

dataSource {
    pooled = false
    driverClassName = "oracle.jdbc.OracleDriver"
    //Add the Dialect for your database
    dialect = org.hibernate.dialect.Oracle10gDialect 
}

hibernate {
    cache.use_second_level_cache = true
    cache.use_query_cache = false
    cache.region.factory_class = 'net.sf.ehcache.hibernate.EhCacheRegionFactory'
    //Set jdbc metadata to false to not open a session
    temp.use_jdbc_metadata_defaults = false
}