How can I make (Spark1.6) saveAsTextFile to append existing file?

Question

In SparkSQL,I use DF.wirte.mode(SaveMode.Append).json(xxxx),but this method get these files like

the filename is too complex and random,I can\'t use

Answer 1

worked on Spark 1.5 , I think this is right usage..

dataframe.write().mode(SaveMode.Append).format(FILE_FORMAT).**partitionBy**("parameter1", "parameter2").save(path);