viirya opened a new issue, #5825:
URL: https://github.com/apache/arrow-datafusion/issues/5825

   ### Describe the bug
   
   When casting from integer to decimal, if casted decimal exceeds the 
precision, e.g. cast(1234567 as decimal(7,3)), DataFusion doesn't handle it so 
the returned decimal is invalid. Whilst in Spark, the cast expression will 
return a null value indicating it's overflowing.
   
   This is due to current behavior of `cast` kernel in arrow-rs. Although it 
checks if division or multiplication overflows in such cast operation, it 
doesn't check precision overflow. This is somehow related to decimal operation 
convention in arrow-rs, that is let user handle invalid values in decimal 
arrays. But for `cast` kernel, because it provides `CastOptions` which defines 
null behavior for invalid case, the behavior of not checking precision overflow 
becomes a bit inconsistent.
   
   Proposed a fix at the upstream: https://github.com/apache/arrow-rs/pull/3996
   
   We can add some tests in DataFusion after new arrow-rs is released.
   
   ### To Reproduce
   
   In datafusion-cli, run the following query:
   ```
   ❯ select cast(1234567 as decimal(7,3));
   +----------------+
   | Int64(1234567) |
   +----------------+
   | 1234.567       |
   +----------------+
   1 row in set. Query took 0.016 seconds.
   
   ### Expected behavior
   
   `cast(1234567 as decimal(7,3))` should return null.
   
   ### Additional context
   
   _No response_


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