fix empty csv cases

xiedeyantu · xiedeyantu · commit 37a99cf981e8 · 2026-03-31T06:59:51.000+08:00
diff --git a/datafusion/expr/src/logical_plan/builder.rs b/datafusion/expr/src/logical_plan/builder.rs
@@ -1987,7 +1987,7 @@ fn project_with_validation(
             }
         }
     }
-    if has_wildcard && projected_expr.is_empty() {
+    if has_wildcard && projected_expr.is_empty() && !plan.schema().fields().is_empty() {
         return plan_err!(
             "SELECT list is empty after resolving * expressions, \
              the wildcard expanded to zero columns"

Original file line number	Diff line number	Diff line change
`@@ -1987,7 +1987,7 @@ fn project_with_validation(`
`1987`	`1987`	`}`
`1988`	`1988`	`}`
`1989`	`1989`	`}`
`1990`		`- if has_wildcard && projected_expr.is_empty() {`
	`1990`	`+ if has_wildcard && projected_expr.is_empty() && !plan.schema().fields().is_empty() {`
`1991`	`1991`	`return plan_err!(`
`1992`	`1992`	`"SELECT list is empty after resolving * expressions, \`
`1993`	`1993`	`the wildcard expanded to zero columns"`