title: How to specify column data type when writing Spark DataFrame to Oracle
body: <p>I want to write a Spark DataFrame to an Oracle table by using Oracle JDBC driver. My code is listed below:</p>
  
  <pre><code>url = "jdbc:oracle:thin:@servername:sid"
  mydf.write \
      .mode("overwrite") \
      .option("truncate", "true") \
      .format("jdbc") \
      .option("url", url) \
      .option("driver", "oracle.jdbc.OracleDriver") \
      .option("createTableColumnTypes", "desc clob, price double") \
      .option("user", "Steven") \
      .option("password", "123456") \
      .option("dbtable", "table1").save()
  </code></pre>
  
  <p>What I want is to specify the desc column to clob type and the price column to double precision type. But Spark show me that the clob type is not supported. The length of desc string is about 30K. I really need your help. Thanks</p>