From 5048204f426da3dbc4674e2acf507dca1ca7e653 Mon Sep 17 00:00:00 2001
From: obdev <obdev@oceanbase.com>
Date: Tue, 15 Nov 2022 07:08:07 +0000
Subject: [PATCH] Fix core of table scan iter

---
 src/sql/engine/expr/ob_expr_to_outfile_row.cpp |  6 +++---
 src/storage/ls/ob_ls_tablet_service.cpp        | 11 +++++------
 src/storage/tx_storage/ob_access_service.cpp   | 11 ++---------
 3 files changed, 10 insertions(+), 18 deletions(-)

diff --git a/src/sql/engine/expr/ob_expr_to_outfile_row.cpp b/src/sql/engine/expr/ob_expr_to_outfile_row.cpp
index db083d61d1..a72eef2134 100644
--- a/src/sql/engine/expr/ob_expr_to_outfile_row.cpp
+++ b/src/sql/engine/expr/ob_expr_to_outfile_row.cpp
@@ -250,9 +250,9 @@ int ObExprToOutfileRow::print_field(char *buf, const int64_t buf_len, int64_t &p
     auto escape_func =
         [buf, buf_len, &pos, need_enclose, &out_info] (ObString &code_point, int32_t wchar) -> int {
       int ret = OB_SUCCESS;
-      if (wchar == '\0') {
-        OZ(out_info.escape_.print_plain_str_literal(buf, buf_len, pos, out_info.print_params_));
-        OZ(print_wchar_to_buf(buf, buf_len, pos, '0', out_info.print_params_.cs_type_));
+      if (wchar == '\0') {
+        OZ(out_info.escape_.print_plain_str_literal(buf, buf_len, pos, out_info.print_params_));
+        OZ(print_wchar_to_buf(buf, buf_len, pos, '0', out_info.print_params_.cs_type_));
       } else if (wchar == out_info.wchar_enclose_ || wchar == out_info.wchar_escape_) {
         OZ(out_info.escape_.print_plain_str_literal(buf, buf_len, pos, out_info.print_params_));
         OZ(copy_string_to_buf(buf, buf_len, pos, code_point));
diff --git a/src/storage/ls/ob_ls_tablet_service.cpp b/src/storage/ls/ob_ls_tablet_service.cpp
index f5fd1b9131..18f940de64 100644
--- a/src/storage/ls/ob_ls_tablet_service.cpp
+++ b/src/storage/ls/ob_ls_tablet_service.cpp
@@ -730,17 +730,16 @@ int ObLSTabletService::table_scan(ObTableScanIterator &iter, ObTableScanParam &p
   } else if (OB_FAIL(get_tablet_with_timeout(param.tablet_id_, data_tablet, param.timeout_))) {
     LOG_WARN("failed to check and get tablet", K(ret), K(param));
   } else if (OB_FAIL(inner_table_scan(data_tablet, iter, param))) {
-    LOG_WARN("failed to do table scan", K(ret), K(param));
+    LOG_WARN("failed to do table scan", K(ret), KP(&iter), K(param));
   } else {
-    result = &iter;
-  }
-
-  if (OB_SUCC(ret)) {
     bool is_same = false;
     allow_to_read_mgr_.check_read_info_same(read_info, is_same);
     if (!is_same) {
       ret = OB_REPLICA_NOT_READABLE;
-      LOG_WARN("ls is not allow to read", K(ret), KPC(ls_));
+      LOG_WARN("ls is not allow to read", K(ret), KPC(ls_), KP(&iter));
+    } else {
+      // result should be assigned at the last
+      result = &iter;
     }
   }
   NG_TRACE(S_table_scan_end);
diff --git a/src/storage/tx_storage/ob_access_service.cpp b/src/storage/tx_storage/ob_access_service.cpp
index a5ca345a3d..69d396794d 100644
--- a/src/storage/tx_storage/ob_access_service.cpp
+++ b/src/storage/tx_storage/ob_access_service.cpp
@@ -271,18 +271,11 @@ int ObAccessService::table_rescan(
     ret = OB_NOT_SUPPORTED;
     LOG_WARN("only table scan iter can be rescan", K(ret), K(result->get_type()));
   } else if (!param.need_switch_param_) {
-    if (ObNewRowIterator::ObTableScanIterator == result->get_type() &&
-        OB_FAIL(static_cast<ObTableScanIterator*>(result)->rescan(param))) {
+    if (OB_FAIL(static_cast<ObTableScanIterator*>(result)->rescan(param))) {
       LOG_WARN("rescan ObTableScanIterator failed", K(ret), K(result), K(vparam));
     }
   } else {
-    ObTableScanIterator *iter = nullptr;
-    if (ObNewRowIterator::ObTableScanIterator == result->get_type()) {
-      iter = static_cast<ObTableScanIterator*>(result);
-    } else {
-      ret = OB_ERR_UNEXPECTED;
-      STORAGE_LOG(WARN, "Unexpected table iter type", K(ret), K(result->get_type()));
-    }
+    ObTableScanIterator *iter =  static_cast<ObTableScanIterator*>(result);
     const share::ObLSID &ls_id = vparam.ls_id_;
     const common::ObTabletID &data_tablet_id = vparam.tablet_id_;
     ObLS *ls = nullptr;