[Fix](predicate pushdown) Common expression not acting on any slot should not be pushed down

be/src/vec/exec/scan/vscan_node.cpp

@@ -17,6 +17,7 @@
 
 #include "vec/exec/scan/vscan_node.h"
 
+#include <gen_cpp/Exprs_types.h>
 #include <gen_cpp/Metrics_types.h>
 #include <gen_cpp/Opcodes_types.h>
 #include <gen_cpp/PaloInternalService_types.h>
@@ -417,19 +418,24 @@ Status VScanNode::_normalize_conjuncts() {
             RETURN_IF_ERROR(_normalize_predicate(conjunct->root(), conjunct.get(), new_root));
             if (new_root) {
                 conjunct->set_root(new_root);
-                if (_should_push_down_common_expr()) {
+                if (_should_push_down_common_expr() &&
+                    VExpr::is_acting_on_a_slot(conjunct->root())) {
+                    // We need to make sure conjunct is acting on a slot before push it down.
+                    // Or it will not be executed by SegmentIterator::_vec_init_lazy_materialization
                     _common_expr_ctxs_push_down.emplace_back(conjunct);
                     it = _conjuncts.erase(it);
                     continue;
                 }
-            } else { // All conjuncts are pushed down as predicate column
+            } else {
+                // Whole conjunct is pushed down as predicate column
                 _stale_expr_ctxs.emplace_back(conjunct);
                 it = _conjuncts.erase(it);
                 continue;
             }
         }
         ++it;
     }
+
     for (auto& it : _slot_id_to_value_range) {
         std::visit(
                 [&](auto&& range) {

be/src/vec/exprs/vexpr.h

@@ -75,6 +75,22 @@ class VExpr {
         return block->columns() - 1;
     }
 
+    static bool is_acting_on_a_slot(const VExprSPtr& expr) {
+        const auto& children = expr->children();
+        const size_t children_size = children.size();
+
+        for (size_t i = 0; i < children_size; ++i) {
+            // If any child expr acts on a column slot
+            // return true immediately.
+            if (is_acting_on_a_slot(children[i])) {
+                return true;
+            }
+        }
+
+        // This is a leaf expression.
+        return expr->node_type() == TExprNodeType::SLOT_REF;
+    }
+
     VExpr(const TExprNode& node);
     VExpr(const VExpr& vexpr);
     VExpr(const TypeDescriptor& type, bool is_slotref, bool is_nullable);

regression-test/data/correctness/test_pushdown_common_expr.out

@@ -22,6 +22,18 @@
 64	g	gg
 8	d	dd
 
+-- !5 --
+256	i	ii
+
+-- !6 --
+
+-- !7 --
+
+-- !8 --
+1024	k	kk
+
+-- !9 --
+
 -- !1 --
 1	a	aa
 128	h	hh
@@ -47,3 +59,15 @@
 64	g	gg
 8	d	dd
 
+-- !5 --
+256	i	ii
+
+-- !6 --
+
+-- !7 --
+
+-- !8 --
+1024	k	kk
+
+-- !9 --
+

regression-test/suites/correctness/test_pushdown_common_expr.groovy

@@ -65,6 +65,44 @@ suite("test_pushdown_common_expr") {
         SELECT * FROM t_pushdown_common_expr WHERE c1 < 300 OR UPPER(c2)="F" OR c3 LIKE "%f%";
     """
 
+    // One conjunct. No push down.
+    order_qt_5 """
+        SELECT * FROM t_pushdown_common_expr WHERE random() > 1 OR uuid_numeric() = 'A' OR c1 = 256
+    """
+
+    // One conjunct. No push down.
+    order_qt_6 """
+        SELECT * FROM t_pushdown_common_expr WHERE random() > 1
+    """
+
+    // Two conjuncts.
+    // random() > 1 is executed by scan node, c1 > 0 is pushed down and executed by segment iterator
+    order_qt_7 """
+        SELECT * FROM t_pushdown_common_expr WHERE random() > 1 AND c1 > 0
+    """
+
+    // One conjunct. No push down.
+    order_qt_8 """
+        SELECT * FROM t_pushdown_common_expr WHERE random() > 1 OR c1 > 1020
+    """
+
+    // t1: 512 & 1024
+    // t2: all
+    // join gets nothing
+    order_qt_9 """
+        SELECT *
+        FROM (
+            SELECT c1
+            FROM t_pushdown_common_expr
+            WHERE c1 >= 512 or random() > 1
+        ) AS t1
+        JOIN (
+            SELECT c1
+            FROM t_pushdown_common_expr
+            WHERE random() = 0
+        ) AS t2 ON t1.c1 = t2.c1
+    """
+
     sql """set enable_common_expr_pushdown=false"""
 
     order_qt_1 """
@@ -83,4 +121,33 @@ suite("test_pushdown_common_expr") {
         SELECT * FROM t_pushdown_common_expr WHERE c1 < 300 OR UPPER(c2)="K" OR c3 LIKE "%k%";
     """
 
-}
+    order_qt_5 """
+        SELECT * FROM t_pushdown_common_expr WHERE random() > 1 OR uuid_numeric() = 'A' OR c1 = 256
+    """
+
+    order_qt_6 """
+        SELECT * FROM t_pushdown_common_expr WHERE random() > 1
+    """
+
+    order_qt_7 """
+        SELECT * FROM t_pushdown_common_expr WHERE random() > 1 AND c1 > 0
+    """
+
+    order_qt_8 """
+        SELECT * FROM t_pushdown_common_expr WHERE random() > 1 OR c1 > 1020
+    """
+
+    order_qt_9 """
+        SELECT *
+        FROM (
+            SELECT c1
+            FROM t_pushdown_common_expr
+            WHERE c1 >= 512 or random() > 1
+        ) AS t1
+        JOIN (
+            SELECT c1
+            FROM t_pushdown_common_expr
+            WHERE random() = 0
+        ) AS t2 ON t1.c1 = t2.c1
+    """
+}