[CP] fix shared expr issue in view merge/query push down

src/sql/rewrite/ob_transform_query_push_down.cpp

@@ -485,6 +485,8 @@ int ObTransformQueryPushDown::check_select_item_push_down(ObSelectStmt *select_s
   int ret = OB_SUCCESS;
   can_be = false;
   bool check_status = false;
+  bool is_select_expr_valid = false;
+  ObSEArray<ObRawExpr*, 8> select_exprs;
   if (OB_ISNULL(select_stmt) || OB_ISNULL(view_stmt)) {
     ret = OB_INVALID_ARGUMENT;
     LOG_WARN("stmt is NULL", K(select_stmt), K(view_stmt), K(ret));
@@ -494,6 +496,13 @@ int ObTransformQueryPushDown::check_select_item_push_down(ObSelectStmt *select_s
     can_be = false;
   } else if (view_stmt->is_contains_assignment() || select_stmt->is_contains_assignment()) {
     can_be = false;
+  } else if (OB_FAIL(view_stmt->get_select_exprs(select_exprs))) {
+    LOG_WARN("failed to get select exprs", K(ret));
+  } else if (OB_FAIL(ObTransformUtils::check_expr_valid_for_stmt_merge(select_exprs,
+                                                                       is_select_expr_valid))) {
+    LOG_WARN("failed to check select expr valid", K(ret));
+  } else if (!is_select_expr_valid) {
+    can_be = false;
   } else if(OB_FAIL(is_select_item_same(select_stmt,
                                         view_stmt,
                                         check_status,

src/sql/rewrite/ob_transform_utils.cpp

@@ -11504,5 +11504,36 @@ int ObTransformUtils::rebuild_win_compare_range_expr(ObRawExprFactory* expr_fact
   return ret;
 }
 
+int ObTransformUtils::check_expr_valid_for_stmt_merge(ObIArray<ObRawExpr*> &select_exprs,
+                                                      bool &is_valid)
+{
+  int ret = OB_SUCCESS;
+  is_valid = true;
+  for (int64_t i = 0; OB_SUCC(ret) && is_valid && i < select_exprs.count(); ++i) {
+    ObRawExpr *expr = select_exprs.at(i);
+    if (OB_ISNULL(expr)) {
+      ret = OB_ERR_UNEXPECTED;
+      LOG_WARN("unexpect null expr", K(ret));
+    } else if (expr->has_flag(IS_CONST) ||
+               expr->has_generalized_column()) {
+      // do nothing
+    } else if (expr->has_flag(CNT_STATE_FUNC) ||
+               expr->has_flag(CNT_USER_VARIABLE) ||
+               expr->has_flag(CNT_ALIAS) ||
+               expr->has_flag(CNT_VALUES) ||
+               expr->has_flag(CNT_SEQ_EXPR) ||
+               expr->has_flag(CNT_SYS_CONNECT_BY_PATH) ||
+               expr->has_flag(CNT_RAND_FUNC) ||
+               expr->has_flag(CNT_SO_UDF) ||
+               expr->has_flag(CNT_PRIOR) ||
+               expr->has_flag(CNT_VOLATILE_CONST) ||
+               expr->has_flag(CNT_ASSIGN_EXPR)) {
+      // the list is aligned with ObRawExprInfoExtractor::not_calculable_expr
+      is_valid = false;
+    }
+  }
+  return ret;
+}
+
 } // namespace sql
 } // namespace oceanbase

src/sql/rewrite/ob_transform_utils.h

@@ -1567,6 +1567,9 @@ public:
   static int rebuild_win_compare_range_expr(ObRawExprFactory* expr_factory,
                                             ObWinFunRawExpr &win_expr,
                                             ObRawExpr* order_expr);
+
+  static int check_expr_valid_for_stmt_merge(ObIArray<ObRawExpr*> &select_exprs,
+                                             bool &is_valid);
 private:
   static int inner_get_lazy_left_join(ObDMLStmt *stmt,
                                       TableItem *table,

src/sql/rewrite/ob_transform_view_merge.cpp

@@ -486,6 +486,8 @@ int ObTransformViewMerge::check_basic_validity(ObDMLStmt *parent_stmt,
   bool has_ref_assign_user_var = false;
   bool force_merge = false;
   bool force_no_merge = false;
+  bool is_select_expr_valid = false;
+  ObSEArray<ObRawExpr*, 8> select_exprs;
   if (OB_ISNULL(parent_stmt) || OB_ISNULL(child_stmt)) {
     ret = OB_ERR_UNEXPECTED;
     LOG_WARN("get unexpected null", K(ret));
@@ -515,6 +517,13 @@ int ObTransformViewMerge::check_basic_validity(ObDMLStmt *parent_stmt,
     LOG_WARN("failed to check has rownum expr", K(ret));
   } else if (has_rownum_expr) {
     can_be = false;
+  } else if (OB_FAIL(child_stmt->get_select_exprs(select_exprs))) {
+    LOG_WARN("failed to get select exprs", K(ret));
+  } else if (OB_FAIL(ObTransformUtils::check_expr_valid_for_stmt_merge(select_exprs,
+                                                                       is_select_expr_valid))) {
+    LOG_WARN("failed to check select expr valid", K(ret));
+  } else if (!is_select_expr_valid) {
+    can_be = false;
   } else if (0 == child_stmt->get_from_item_size()) {
     //当 view 为 select ... from dual, 若上层非层次查询, 允许视图合并
     can_be = parent_stmt->is_single_table_stmt()

tools/deploy/mysql_test/test_suite/static_engine/t/expr_sign.test

+--source mysql_test/include/explain_init.inc
 # owner: dachuan.sdc
 # owner group: sql2
 # tags: optimizer
@@ -149,3 +150,4 @@ select sign( cast(a2 as char(1024)) ) , sign( cast(a4 as char(1024)) ) from t2 f
 --echo #https://work.aone.alibaba-inc.com/issue/32398792
 select sign(1E-300) from dual;
 select sign(1E-400) from dual;
+--source mysql_test/include/explain_end.inc