diff --git a/src/include/transaction_mainenance.hpp b/src/include/transaction_mainenance.hpp
index b90b500..cee21e7 100644
--- a/src/include/transaction_mainenance.hpp
+++ b/src/include/transaction_mainenance.hpp
@@ -6,14 +6,16 @@
 #include "data.h"
 #include "storage/bpt.hpp"
 #include "storage/buffer_pool_manager.h"
+#include "storage/config.h"
 #include "storage/disk_manager.h"
 #include "storage/driver.h"
 #include "storage/single_value_storage.hpp"
+#include "utils.h"
 struct TransactionData {
   char trainID[21];
   char from_station_name[41];
   char to_station_name[41];
-  uint8_t status;
+  uint8_t status;  // 0: in queue, 1: success, 2: refunded
   uint32_t leave_time_stamp;
   uint32_t arrive_time_stamp;
   uint32_t num;
@@ -126,5 +128,98 @@ class TransactionManager : public DataDriverBase {
     queue_indexer->Flush();
     order_history_indexer->Flush();
   }
+  inline void AddOrder(std::string trainID, std::string from_station_name, std::string to_station_name, uint8_t status,
+                       uint32_t leave_time_stamp, uint32_t arrive_time_stamp, uint32_t num, uint64_t total_price,
+                       uint8_t running_date_offset) {
+    TransactionData tmp;
+    strcpy(tmp.trainID, trainID.c_str());
+    strcpy(tmp.from_station_name, from_station_name.c_str());
+    strcpy(tmp.to_station_name, to_station_name.c_str());
+    tmp.status = status;
+    tmp.leave_time_stamp = leave_time_stamp;
+    tmp.arrive_time_stamp = arrive_time_stamp;
+    tmp.num = num;
+    tmp.total_price = total_price;
+    b_plus_tree_value_index_t data_id = data_storage->write(tmp);
+    hash_t train_ID_hash = SplitMix64Hash(trainID);
+    if (status == 0) {
+      queue_index_t queue_index_for_query;
+      queue_index_for_query.train_ID_hash = train_ID_hash;
+      queue_index_for_query.running_offset = running_date_offset;
+      queue_index_for_query.id = queue_index_specai_id;
+      int new_id;
+      {
+        auto it_queue_query = queue_indexer->lower_bound(queue_index_for_query);
+        new_id = it_queue_query.GetValue() + 1;
+        it_queue_query.SetValue(new_id);
+      }  // to release the lock
+      queue_index_t queue_index;
+      queue_index.train_ID_hash = queue_index_for_query.train_ID_hash;
+      queue_index.running_offset = running_date_offset;
+      queue_index.id = new_id;
+      queue_indexer->Put(queue_index, data_id);
+    }
+    order_history_index_t order_history_index_for_query;
+    order_history_index_for_query.user_ID_hash = train_ID_hash;
+    order_history_index_for_query.id = order_history_index_special_id;
+    int new_id;
+    {
+      auto it_order_history_query = order_history_indexer->lower_bound(order_history_index_for_query);
+      new_id = it_order_history_query.GetValue() + 1;
+      it_order_history_query.SetValue(new_id);
+    }  // to release the lock
+    order_history_index_t order_history_index;
+    order_history_index.user_ID_hash = train_ID_hash;
+    order_history_index.id = new_id;
+    order_history_indexer->Put(order_history_index, data_id);
+  }
+  inline void FetchQueue(hash_t train_ID_hash, uint8_t running_date_offset,
+                         std::vector<b_plus_tree_value_index_t> &res) {
+    // warning: the validity of train_ID_hash is not checked
+    queue_index_t queue_index_for_query;
+    queue_index_for_query.train_ID_hash = train_ID_hash;
+    queue_index_for_query.running_offset = running_date_offset;
+    queue_index_for_query.id = queue_index_specai_id;
+    auto it = queue_indexer->lower_bound_const(queue_index_for_query);
+    int total_num = it.GetValue();
+    res.resize(total_num);
+    for (int i = 0; i < total_num; i++) {
+      ++it;
+      res[i] = it.GetValue();
+    }
+  }
+  inline void FetchFullUserOrderHistory(hash_t user_ID_hash, std::vector<b_plus_tree_value_index_t> &res) {
+    // warning: the validity of user_ID_hash is not checked
+    order_history_index_t order_history_index_for_query;
+    order_history_index_for_query.user_ID_hash = user_ID_hash;
+    order_history_index_for_query.id = order_history_index_special_id;
+    auto it = order_history_indexer->lower_bound_const(order_history_index_for_query);
+    int total_num = it.GetValue();
+    res.resize(total_num);
+    for (int i = 0; i < total_num; i++) {
+      ++it;
+      res[i] = it.GetValue();
+    }
+  }
+  inline b_plus_tree_value_index_t FetchSingleUserOrderHistory(hash_t user_ID_hash, int n, bool &success) {
+    // warning: the validity of user_ID_hash is not checked
+    order_history_index_t order_history_index_for_query;
+    order_history_index_for_query.user_ID_hash = user_ID_hash;
+    order_history_index_for_query.id = order_history_index_special_id;
+    auto it = order_history_indexer->lower_bound_const(order_history_index_for_query);
+    int total_num = it.GetValue();
+    if (n > total_num) {
+      success = false;
+      return 0;
+    }
+    order_history_index_for_query.id = total_num - n + 1;
+    auto dat_it = order_history_indexer->lower_bound_const(order_history_index_for_query);
+    success = true;
+    return dat_it.GetValue();
+  }
+  inline void FetchTransactionData(b_plus_tree_value_index_t idx, TransactionData &data) {
+    // warning: the validity of idx is not checked
+    data_storage->read(data, idx);
+  }
 };
 #endif
\ No newline at end of file
diff --git a/storage/include/storage/disk_multimap.hpp b/storage/include/storage/disk_multimap.hpp
deleted file mode 100644
index e69de29..0000000