diff --git a/src/sql/ob_spi.cpp b/src/sql/ob_spi.cpp
index 2a35eff49d..777be66a71 100644
--- a/src/sql/ob_spi.cpp
+++ b/src/sql/ob_spi.cpp
@@ -257,6 +257,23 @@ int ObSPIResultSet::is_set_global_var(ObSQLSessionInfo &session, const ObString
       } else if (T_VAR_VAL == set_node->type_ &&
                  1 == set_node->value_) { // global var
         has_global_variable = true;
+      } else if (set_node->num_child_ > 0 && OB_NOT_NULL(set_node->children_[0])) {
+        ParseNode *var = set_node->children_[0];
+        ObString name;
+        if (T_OBJ_ACCESS_REF == var->type_) { //Oracle mode
+          const ParseNode *name_node = NULL;
+          if (OB_ISNULL(name_node = var->children_[0])) {
+            ret = OB_ERR_UNEXPECTED;
+            LOG_WARN("get unexpected null", K(ret));
+          } else {
+            name.assign_ptr(name_node->str_value_, static_cast<int32_t>(name_node->str_len_));
+          }
+        } else if (T_SYSTEM_VARIABLE == var->type_) {
+          name.assign_ptr(var->str_value_, static_cast<int32_t>(var->str_len_));
+        }
+        if (OB_SUCC(ret) && 0 == name.case_compare("ob_query_timeout")) {
+          has_global_variable = true;
+        }
       }
     }
   }
diff --git a/src/sql/ob_sql.cpp b/src/sql/ob_sql.cpp
index d7cb0ae761..e21c8eeb01 100644
--- a/src/sql/ob_sql.cpp
+++ b/src/sql/ob_sql.cpp
@@ -1199,10 +1199,6 @@ ObSql::TimeoutGuard::TimeoutGuard(ObSQLSessionInfo &session)
 {
   int ret = OB_SUCCESS;
   worker_timeout_ = THIS_WORKER.get_timeout_ts();
-  if (OB_FAIL(session_.get_query_timeout(query_timeout_))
-      || OB_FAIL(session_.get_tx_timeout(trx_timeout_))) {
-    LOG_ERROR("get timeout failed", KR(ret), K(query_timeout_), K(trx_timeout_));
-  }
 }
 
 ObSql::TimeoutGuard::~TimeoutGuard()
@@ -1211,24 +1207,6 @@ ObSql::TimeoutGuard::~TimeoutGuard()
   if (THIS_WORKER.get_timeout_ts() != worker_timeout_) {
     THIS_WORKER.set_timeout_ts(worker_timeout_);
   }
-  int64_t query_timeout = 0;
-  int64_t trx_timeout = 0;
-  if (OB_FAIL(session_.get_query_timeout(query_timeout))
-      || OB_FAIL(session_.get_tx_timeout(trx_timeout))) {
-    LOG_ERROR("get timeout failed", KR(ret), K(query_timeout), K(trx_timeout));
-  } else {
-    if (query_timeout != query_timeout_ || trx_timeout != trx_timeout_) {
-      ObObj query_val, trx_val;
-      query_val.set_int(query_timeout_);
-      trx_val.set_int(trx_timeout_);
-      if (OB_FAIL(ret)) {
-      } else if (OB_FAIL(session_.update_sys_variable(SYS_VAR_OB_QUERY_TIMEOUT, query_val))) {
-        LOG_WARN("set sys variable failed", K(ret), K(OB_SV_QUERY_TIMEOUT), K(query_val));
-      } else if (OB_FAIL(session_.update_sys_variable(SYS_VAR_OB_TRX_TIMEOUT, trx_val))) {
-        LOG_WARN("set sys variable failed", K(ret), K(OB_SV_TRX_TIMEOUT), K(trx_val));
-      }
-    }
-  }
 }
 
 int ObSql::set_timeout_for_pl(ObSQLSessionInfo &session_info, int64_t &abs_timeout_us)
diff --git a/src/sql/ob_sql.h b/src/sql/ob_sql.h
index 964e95cf69..d60ea90327 100644
--- a/src/sql/ob_sql.h
+++ b/src/sql/ob_sql.h
@@ -245,8 +245,6 @@ private:
   private:
     ObSQLSessionInfo &session_;
     int64_t worker_timeout_;
-    int64_t query_timeout_;
-    int64_t trx_timeout_;
   };
 
 private:
diff --git a/tools/deploy/mysql_test/test_suite/pl/r/mysql/pl_basic_mysql.result b/tools/deploy/mysql_test/test_suite/pl/r/mysql/pl_basic_mysql.result
index 9603a381b2..339a00c825 100644
--- a/tools/deploy/mysql_test/test_suite/pl/r/mysql/pl_basic_mysql.result
+++ b/tools/deploy/mysql_test/test_suite/pl/r/mysql/pl_basic_mysql.result
@@ -484,7 +484,7 @@ select @@session.ob_trx_timeout;
 +--------------------------+
 | @@session.ob_trx_timeout |
 +--------------------------+
-|                100000000 |
+|                100000001 |
 +--------------------------+
 set @@session.ob_trx_timeout=100000000;