Extending multiple grails DataSources in DataSources.groovy?
dataSource1 {
    dbCreate = "update"
    dialect = org.hibernate.dialect.Oracle10gDialect
    pooled = false
    jndiName = "java:something"
}
dataSource2 {
            pooled = true
            driverClassName = "org.hsqldb.jdbcDriver"
            username = "sa"
            password = ""
            dbCreate = "update"
            url = "jdbc:hsqldb:mem:testDb"
}

// environment specific settings
environments {
    //extend datasource1
    production{
    }
    //extend datasource2
    development{
    }
}

dataSource1 = {
    dbCreate = "update"
    driverClassName = "org.hsqldb.jdbcDriver"
    dialect = org.hibernate.dialect.Oracle10gDialect
    pooled = false
    jndiName = "java:something"
}

dataSource2 = {
            pooled = true
            driverClassName = "org.hsqldb.jdbcDriver"
            username = "sa"
            password = ""
            dbCreate = "update"
            url = "jdbc:hsqldb:mem:testDb"
}

environments {
    production {
        dataSource {
            dataSource1.call()
        }
    }
    development {
        dataSource {
            dataSource2.call()
        }
    }
}

environments {
   production {
      dataSource {
         dbCreate = "update"
         dialect = org.hibernate.dialect.Oracle10gDialect
         pooled = false
         jndiName = "java:something"
      }
   }
}

if (System.properties["${appName}.config.location"]) {
    grails.config.locations = ["file:" + System.properties["${appName}.config.location"]]
}