vbarua commented on code in PR #15854: URL: https://github.com/apache/datafusion/pull/15854#discussion_r2067014140
########## datafusion/substrait/src/logical_plan/producer.rs: ########## @@ -1590,6 +1590,21 @@ pub fn from_cast( schema: &DFSchemaRef, ) -> Result<Expression> { let Cast { expr, data_type } = cast; + // since substrait Null must be typed, so if we see a cast(null, dt), we make it a typed null + if let Expr::Literal(lit) = expr.as_ref() { + if lit.is_null() { Review Comment: To further clarify, at the SQL/Relational level ```sql SELECT null::text[], array[]::text[] text | array ---- | -- null | {} ``` we can distinguish between casting a null literal to a compound type, and the empty version of that compound type. [dbfiddle](https://www.db-fiddle.com/f/cH7Hwk6mHnm3rgy7wXG4Yq/47) -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: github-unsubscr...@datafusion.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: github-unsubscr...@datafusion.apache.org For additional commands, e-mail: github-h...@datafusion.apache.org