liukun4515 commented on PR #5605:
URL: https://github.com/apache/arrow-rs/pull/5605#issuecomment-2058139684

   > > We need to add the timezone config in the CastOptions which can't be 
configured by other system like datafusion.
   > 
   > The conversion should take the date of the timestamp in the timezone 
configured on the timestamp data type, we should not need to configure this on 
`CastOptions`, we have very carefully avoided introducing the notion of a 
"local" timezone.
   > 
   > So for example if we had `2019-10-12T07:20:50.52 +10:00`, the date 
returned would be `2019-10-12` even though with reference to the UTC epoch 
(which is what the timestamp integer encodes) the date would be `2019-10-11`.
   
   
   
   Hi  @tustvold 
   From the definition of the timestamp in the arrow schema: 
https://github.com/apache/arrow/blob/main/format/Schema.fbs#L283
   
   It's will cause inconvenient usage, let me give a example:
   
   When I write a parquet file with timestamp column using the spark engine, 
the timestamp column is encoded by 
https://github.com/apache/parquet-format/blob/master/LogicalTypes.md#instant-semantics-timestamps-normalized-to-utc
 and is normalized to UTC.
   
   But when I use arrow-parquet to read the timestamp column, i will just get 
the column with timestamp(unit, "UTC") data type by this code 
https://github.com/apache/arrow-rs/blob/0d031cc8aa81296cb1bdfedea7a7cb4ec6aa54ea/parquet/src/arrow/schema/primitive.rs#L86
 and 
https://github.com/apache/arrow-rs/blob/0d031cc8aa81296cb1bdfedea7a7cb4ec6aa54ea/parquet/src/arrow/schema/primitive.rs#L232
   
   It's even possible to use `int96` to store the timestamp in the parquet 
file, we will get the column with timestamp(nanosecond, None) data type by 
https://github.com/apache/arrow-rs/blob/0d031cc8aa81296cb1bdfedea7a7cb4ec6aa54ea/parquet/src/arrow/schema/primitive.rs#L99
   
   But i need this is used in the  `UTC-7` timezone, how did you resolve this 
issue? @alamb 


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