RisingWave Community - Why does psycopg2 return an error with sum() but not with count() in a query involving a materialized view?

The issue you are facing with psycopg2 when using sum() in a query involving a materialized view is likely due to a version problem or a compatibility issue.
The error 'psycopg2.DataError: array does not start with '{'' suggests that there might be an unexpected array data format being returned by the query.
It's possible that the sum() function in psycopg2 is handling the data differently compared to count(), leading to this error.
Check the version of psycopg2 you are using and consider trying different versions to see if the issue persists.
Ensure that there are no array data types in the columns of the materialized view that could be causing this error.