Hi Ying,
Le 28/01/2021 à 08:15, Ying Zhou a écrit : > > > By the way I haven’t found any function that can directly generate an Arrow > Table using a schema, size and null_probability. Is there any need for such > functionality? If this is useful for purposes beyond ORC/Parquet/CSV/etc IO > maybe we should write one. Yes, that would probably be generally useful for testing. > For the latter what I need is a table converter that can recursively convert > every instance of LargeBinary and FixedSizeBinary into Binary, every instance > of LargeString into String, every instance of Date64 into Timestamp (unit = > MILLI), every instance of LargeList and FixedSizeList into List and maybe > every instance of Map into List of Structs in a table to independently > produce the expected ORCReader(ORCWriter(Table)) so that I can verify that > the ORCWriter is working as intended. For this problem I have at least two > possible approaches: either perform the conversion mainly at array level or > do so mainly at scalar level. Do you know the Cast() API? See arrow/compute/cast.h for details. Regards Antoine.
