[fix](agg)fix group by constant value bug (#13827)

* [fix](agg)fix group by constant value bug

* keep only one const grouping exprs if no agg exprs

fe/fe-core/src/main/java/org/apache/doris/analysis/SelectStmt.java

@@ -1092,8 +1092,13 @@ public class SelectStmt extends QueryStmt {
 
             substituteOrdinalsAliases(groupingExprs, "GROUP BY", analyzer);
 
-            if (!groupByClause.isGroupByExtension()) {
+            if (!groupByClause.isGroupByExtension() && !groupingExprs.isEmpty()) {
+                ArrayList<Expr> tempExprs = new ArrayList<>(groupingExprs);
                 groupingExprs.removeIf(Expr::isConstant);
+                if (groupingExprs.isEmpty() && aggExprs.isEmpty()) {
+                    // should keep at least one expr to make the result correct
+                    groupingExprs.add(tempExprs.get(0));
+                }
             }
 
             if (groupingInfo != null) {

regression-test/data/trino_p0/sql/group_by/runConstantGroupBy_order.out

@@ -1,28 +1,4 @@
 -- This file is automatically generated. You should know what you did if you want to edit this
 -- !runConstantGroupBy_order --
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