[GitHub] [arrow-datafusion] jackwener commented on a diff in pull request #6799: fix: incorrect nullability of `InList` expr

["jackwener (via GitHub)" <gi...@apache.org>]

jackwener commented on code in PR #6799:
URL: https://github.com/apache/arrow-datafusion/pull/6799#discussion_r1247648888


##########
datafusion/expr/src/expr_schema.rs:
##########
@@ -173,8 +173,30 @@ impl ExprSchemable for Expr {
             Expr::Alias(expr, _)
             | Expr::Not(expr)
             | Expr::Negative(expr)
-            | Expr::Sort(Sort { expr, .. })
-            | Expr::InList(InList { expr, .. }) => expr.nullable(input_schema),
+            | Expr::Sort(Sort { expr, .. }) => expr.nullable(input_schema),
+
+            Expr::InList(InList { expr, list, .. }) => {
+                // Avoid inspecting too many expressions.
+                const MAX_INSPECT_LIMIT: usize = 6;

Review Comment:
   I want to know why use this number? Is it the practice from other systems?



##########
datafusion/expr/src/expr_schema.rs:
##########
@@ -173,8 +173,30 @@ impl ExprSchemable for Expr {
             Expr::Alias(expr, _)
             | Expr::Not(expr)
             | Expr::Negative(expr)
-            | Expr::Sort(Sort { expr, .. })
-            | Expr::InList(InList { expr, .. }) => expr.nullable(input_schema),
+            | Expr::Sort(Sort { expr, .. }) => expr.nullable(input_schema),
+
+            Expr::InList(InList { expr, list, .. }) => {
+                // Avoid inspecting too many expressions.
+                const MAX_INSPECT_LIMIT: usize = 6;

Review Comment:
   spark handle it simplified.
   
   ```scala
   override def nullable: Boolean = children. Exists(_.nullable)
   ```



-- 
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-unsubscribe@arrow.apache.org

For queries about this service, please contact Infrastructure at:
users@infra.apache.org