I have a similar problem. getting the error message: NULL result in a non-nullable column on my loading my parquet files.
I have NOT null columns in Snowflake for example, NAME2, NAME3, but the values against them in the parquet files are empty string.
So my question is how can I resolve this constraint without changing my table definition or without removing not null constraint?
COPY INTO "DB_STAGE"."SCH_ABC_INIT"."T_TAB" FROM ( SELECT $1:OPSYS::VARCHAR, $1:MANDT::VARCHAR, $1:LIFNR::VARCHAR, $1:LAND1::VARCHAR, $1:NAME1::VARCHAR, $1:NAME2::VARCHAR, $1:NAME3::VARCHAR, $1:NAME4::VARCHAR, .. .. $1:OPTYPE::VARCHAR FROM @DB_STAGE.SCH_ABC_INIT.initial_load_stage_ABC) file_format = (type = 'parquet', NULL_IF=('NULL','',' ','NULL','NULL','//N')) pattern = '.*/ABC-TAB-prod/.*snappy.parquet';