complete function: Get_fields

db/db_impl.cc

@@ -1180,15 +1180,6 @@ Status DBImpl::Get(const ReadOptions& options, const Slice& key,
   mem->Unref();
   if (imm != nullptr) imm->Unref();
   current->Unref();
-
-  // TODO(begin): search the slotpage and get value from vlog
-  size_t slot_num = *(size_t *)value->c_str();
-  struct slot_content sc;
-  std::string vlog_value;
-  slot_page_->get_slot(slot_num, &sc);
-  vlog_set_->get_value(sc.vlog_num, sc.value_offset, &vlog_value);
-  *value = vlog_value;
-  // TODO(end)
   return s;
 }
 
@@ -1200,6 +1191,18 @@ Status DBImpl::Get_Fields(const ReadOptions& options, const Slice& key,
   if (!s.ok()) {
     return s;
   }
+  // 从value中提取slot_num
+  size_t slot_num;
+    slot_num = *(size_t *)value.c_str();  // 这里假设value的前几个字节存储了slot_num
+  struct slot_content sc;
+  std::string vlog_value;
+  // 从slot_page中获取slot内容
+  slot_page_->get_slot(slot_num, &sc);
+  // 从vlog_set中获取实际的日志值
+  vlog_set_->get_value(sc.vlog_num, sc.value_offset, &vlog_value);
+  // 更新value为从vlog获取的值
+  value = vlog_value;
+
   std::cout << "value from value_log: " << key.ToString() << value << std::endl;
   *fields = DeserializeValue(value);
   return Status::OK();

test/db_test3.cc

@@ -175,9 +175,13 @@ TEST(TestSchema, Basic) {
     std::cerr << "open db failed" << std::endl;
     abort();
   }
+  std::string key = "key";
+  std::string key0 = "k_0";
   std::string key1 = "k_1";
   std::string key2 = "k_2";
   std::string key3 = "k_3";
+  std::string value = "value";
+  FieldArray fields0 = {{"name", "wxf"}};
   FieldArray fields1 = {
       {"name", "Customer1"},
       {"address", "IVhzIApeRb"},
@@ -194,21 +198,33 @@ TEST(TestSchema, Basic) {
       {"address", "ecnu"},
       {"phone", "11111"}
   };
+  db->Put(writeOptions, key, value);
+  std::cout << "put_value: " << value << std::endl;
+  db->Put_Fields(leveldb::WriteOptions(), key0, fields0);
   db->Put_Fields(leveldb::WriteOptions(), key1, fields1);
   db->Put_Fields(leveldb::WriteOptions(), key2, fields2);
   db->Put_Fields(leveldb::WriteOptions(), key3, fields3);
-
-  // 读取并反序列化
   std::string value_ret;
-  FieldArray fields_ret;
-  db->Get_Fields(leveldb::ReadOptions(), key1, &fields_ret);
+  db->Get(readOptions, key, &value_ret);
+  std::cout << "get_value: " << value_ret << std::endl;
+  // 读取并反序列化
+  FieldArray fields_ret_0;
+  FieldArray fields_ret_1;
+  db->Get_Fields(leveldb::ReadOptions(), key0, &fields_ret_0);
+  db->Get_Fields(leveldb::ReadOptions(), key1, &fields_ret_1);
 
 
   // 检查反序列化结果
-  ASSERT_EQ(fields_ret.size(), fields1.size());
-  for (size_t i = 0; i < fields_ret.size(); ++i) {
-    ASSERT_EQ(fields_ret[i].name, fields1[i].name);
-    ASSERT_EQ(fields_ret[i].value, fields1[i].value);
+  ASSERT_EQ(fields_ret_0.size(), fields0.size());
+  for (size_t i = 0; i < fields_ret_0.size(); ++i) {
+    ASSERT_EQ(fields_ret_0[i].name, fields1[i].name);
+    ASSERT_EQ(fields_ret_0[i].value, fields1[i].value);
+  }
+
+  ASSERT_EQ(fields_ret_1.size(), fields1.size());
+  for (size_t i = 0; i < fields_ret_1.size(); ++i) {
+    ASSERT_EQ(fields_ret_1[i].name, fields1[i].name);
+    ASSERT_EQ(fields_ret_1[i].value, fields1[i].value);
   }
 
   // 测试查找功能