val dataframe_oracle = sqlContext.read.format("jdbc").option("url", dbUrl).option("driver", "oracle.jdbc.driver.OracleDriver").option("dbtable", sqlQuery).option("user", dbUserName).option("password", dbPassword).load

Stu _id   Percent
1         80.145
2         60.34

Stu _id   Percent
1         0E+127
2         0E+127

var connection: Connection = null
      val driver = "oracle.jdbc.driver.OracleDriver"
      Class.forName(driver)

      var dbURL: String = "jdbc:oracle:thin:@//" + dbServer + ":" + dbPort + "/" + dbName //+localhost:1521/xe"

      connection = DriverManager.getConnection(dbURL, dbUsername, dbpassword)
      val DBMetaData = connection.getMetaData();