fix reroute check for single sql in trans

src/observer/mysql/obmp_query.cpp

@@ -340,8 +340,10 @@ int ObMPQuery::process()
                 // 但是目前的代码实现难以在不同的线程处理同一个请求的回包，
                 // 因此这里只允许只有一个query的multi query请求异步回包。
                 force_sync_resp = queries.count() <= 1? false : true;
-                bool is_single_stmt = queries.count() <= 1? true : false;
+                // is_part_of_multi 表示当前sql是 multi stmt 中的一条，
-                ret = process_single_stmt(ObMultiStmtItem(true, i, queries.at(i), is_single_stmt),
+                // 原来的值默认为true，会影响单条sql的二次路由，现在改为用 queries.count() 判断。
+                bool is_part_of_multi = queries.count() > 1 ? true : false;
+                ret = process_single_stmt(ObMultiStmtItem(is_part_of_multi, i, queries.at(i)),
                                           session,
                                           has_more,
                                           force_sync_resp,

src/sql/ob_sql.cpp

@@ -5146,8 +5146,7 @@ int ObSql::check_need_reroute(ObPlanCacheCtx &pc_ctx, ObSQLSessionInfo &session,
     if (should_reroute && !session.is_inner() && session.is_in_transaction()) {
       auto stmt_type = plan->get_stmt_type();
       bool fixed_route = true;
-      if (pc_ctx.sql_ctx_.multi_stmt_item_.is_part_of_multi_stmt()
+      if (pc_ctx.sql_ctx_.multi_stmt_item_.is_part_of_multi_stmt()) {
-          && !pc_ctx.sql_ctx_.multi_stmt_item_.is_single_stmt()) {
         // current is multi-stmt
       } else if (!STMT_SUPPORT_BY_TXN_FREE_ROUTE(stmt_type, false)) {
         // stmt is not DML

src/sql/ob_sql_context.h

@@ -163,19 +163,17 @@ public:
       batched_queries_(NULL),
       is_ins_multi_val_opt_(false),
       is_ps_mode_(false),
-      ab_cnt_(0),
+      ab_cnt_(0)
-      is_single_stmt_(false)
   {
   }
-  ObMultiStmtItem(bool is_part_of_multi, int64_t seq_num, const common::ObString &sql, bool is_single_stmt=false)
+  ObMultiStmtItem(bool is_part_of_multi, int64_t seq_num, const common::ObString &sql)
     : is_part_of_multi_stmt_(is_part_of_multi),
       seq_num_(seq_num),
       sql_(sql),
       batched_queries_(NULL),
       is_ins_multi_val_opt_(false),
       is_ps_mode_(false),
-      ab_cnt_(0),
+      ab_cnt_(0)
-      is_single_stmt_(is_single_stmt)
   {
   }
 
@@ -190,8 +188,7 @@ public:
       batched_queries_(queries),
       is_ins_multi_val_opt_(is_multi_vas_opt),
       is_ps_mode_(false),
-      ab_cnt_(0),
+      ab_cnt_(0)
-      is_single_stmt_(false)
   {
   }
   virtual ~ObMultiStmtItem() {}
@@ -203,7 +200,6 @@ public:
     sql_.reset();
     batched_queries_ = NULL;
     is_ins_multi_val_opt_ = false;
-    is_single_stmt_ = false;
   }
 
   inline bool is_part_of_multi_stmt() const { return is_part_of_multi_stmt_; }
@@ -238,10 +234,9 @@ public:
   inline bool is_ps_mode() { return is_ps_mode_; }
   inline void set_ab_cnt(int64_t cnt) { ab_cnt_ = cnt; }
   inline int64_t get_ab_cnt() { return ab_cnt_; }
-  inline bool is_single_stmt() const { return is_single_stmt_; }
 
-  TO_STRING_KV(K_(is_part_of_multi_stmt), K_(seq_num), K_(sql), KPC_(batched_queries),
+  TO_STRING_KV(K_(is_part_of_multi_stmt), K_(seq_num), K_(sql),
-               K_(is_ins_multi_val_opt), K_(is_ps_mode), K_(ab_cnt), K_(is_single_stmt));
+               KPC_(batched_queries), K_(is_ins_multi_val_opt), K_(is_ps_mode), K_(ab_cnt));
 
 private:
   bool is_part_of_multi_stmt_; // 是否为multi stmt，非multi stmt也使用这个结构体，因此需要这个标记
@@ -252,7 +247,6 @@ private:
   bool is_ins_multi_val_opt_;
   bool is_ps_mode_;
   int64_t ab_cnt_;
-  bool is_single_stmt_;
 };
 
 class ObQueryRetryInfo