What does dataframe saveAsTable(Append mode) do when target table has the different data type with current dataframe schema. for example:
> val df = Seq((1L,1),(2L,1),(3L,1),(456789234L,1)).toDF("i","p")
> df.printSchema
root
|-- i: long (nullable = false)
|-- p: integer (nullable = false)
> df.write.mode("append").format("hive").partitionBy("p").saveAsTable("default.ljh_test2")
and the existing hive table is created by:
CREATE TABLE default.ljh_test2 (i int) PARTITIONED BY (p int) STORED AS ORC;
it seems the dataframe could write the data to hive table, but the column i is bigint in dataframe but int int hive.
I want to know how does the spark dataframe do the data type cast, where can I find he relevant docs.
Thanks.
