diff --git a/CMakeLists.txt b/CMakeLists.txt
index fd98cb6..3b03133 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -529,4 +529,10 @@ target_link_libraries(db_test2 PRIVATE leveldb)
 add_executable(ttl_test
         "${PROJECT_SOURCE_DIR}/test/ttl_test.cc"
 )
-target_link_libraries(ttl_test PRIVATE leveldb gtest)
\ No newline at end of file
+target_link_libraries(ttl_test PRIVATE leveldb gtest)
+
+
+add_executable(simple_test
+        "${PROJECT_SOURCE_DIR}/test/simple_test.cc"
+)
+target_link_libraries(simple_test PRIVATE leveldb gtest)
\ No newline at end of file
diff --git a/db/db_impl.cc b/db/db_impl.cc
index 8eb536c..0d5e730 100644
--- a/db/db_impl.cc
+++ b/db/db_impl.cc
@@ -4,14 +4,6 @@
 
 #include "db/db_impl.h"
 
-#include <algorithm>
-#include <atomic>
-#include <cstdint>
-#include <cstdio>
-#include <set>
-#include <string>
-#include <vector>
-
 #include "db/builder.h"
 #include "db/db_iter.h"
 #include "db/dbformat.h"
@@ -22,11 +14,21 @@
 #include "db/table_cache.h"
 #include "db/version_set.h"
 #include "db/write_batch_internal.h"
+#include <algorithm>
+#include <atomic>
+#include <cstdint>
+#include <cstdio>
+#include <iostream>
+#include <set>
+#include <string>
+#include <vector>
+
 #include "leveldb/db.h"
 #include "leveldb/env.h"
 #include "leveldb/status.h"
 #include "leveldb/table.h"
 #include "leveldb/table_builder.h"
+
 #include "port/port.h"
 #include "table/block.h"
 #include "table/merger.h"
@@ -1162,6 +1164,15 @@ Status DBImpl::Get(const ReadOptions& options, const Slice& key,
   mem->Unref();
   if (imm != nullptr) imm->Unref();
   current->Unref();
+  if(s.ok()){
+    auto a = env_->GetCurrentTime();
+    auto b = GetTS(value);
+    std::cout<< "read when      " << a<<std::endl;
+    std::cout<< "read timestamp "<<b << std::endl;
+    if(env_->GetCurrentTime() > GetTS(value)){
+      return Status::Expire("Expire",Slice());
+    }
+  }
   return s;
 }
 
@@ -1475,7 +1486,6 @@ void DBImpl::GetApproximateSizes(const Range* range, int n, uint64_t* sizes) {
   MutexLock l(&mutex_);
   Version* v = versions_->current();
   v->Ref();
-
   for (int i = 0; i < n; i++) {
     // Convert user_key into a corresponding internal key.
     InternalKey k1(range[i].start, kMaxSequenceNumber, kValueTypeForSeek);
@@ -1484,7 +1494,6 @@ void DBImpl::GetApproximateSizes(const Range* range, int n, uint64_t* sizes) {
     uint64_t limit = versions_->ApproximateOffsetOf(v, k2);
     sizes[i] = (limit >= start ? limit - start : 0);
   }
-
   v->Unref();
 }
 
@@ -1503,6 +1512,12 @@ void DBImpl::AppendTS(const Slice& val, std::string* val_with_ts,uint64_t ttl) {
   val_with_ts->append(reinterpret_cast<const char*>(&st), sizeof(st));
 }
 
+uint64_t DBImpl::GetTS(const std::string* val) {
+    uint64_t expiration_time;
+    memcpy(&expiration_time, val->data() + val->size() - sizeof(uint64_t), sizeof(uint64_t));
+    return expiration_time;
+}
+
 /**
  *
  * @param options
@@ -1521,14 +1536,16 @@ Status DB::Put(const WriteOptions& options, const Slice& key,
 
   uint64_t expiration_time = std::chrono::duration_cast<std::chrono::milliseconds>(
                                  std::chrono::system_clock::now().time_since_epoch())
-                                 .count(); + ttl;
+                                 .count() + ttl;
 
   // 追加原始 value 到 val_with_ts
   val_with_ts.append(value.data(), value.size());
 
   // 将 expiration_time 追加到 val_with_ts
   val_with_ts.append(reinterpret_cast<const char*>(&expiration_time), sizeof(expiration_time));
-
+  std::cout<<"PUT"<<std::endl;
+  std::cout << "timestamp: " << expiration_time << std::endl;
+  //"a\323='\277\222\001\000"
   WriteBatch batch;
   batch.Put(key, Slice(val_with_ts));
   return Write(options, &batch);
diff --git a/db/db_impl.h b/db/db_impl.h
index 2517e7f..1d63516 100644
--- a/db/db_impl.h
+++ b/db/db_impl.h
@@ -52,6 +52,7 @@ class DBImpl : public DB {
   void GetApproximateSizes(const Range* range, int n, uint64_t* sizes) override;
   void CompactRange(const Slice* begin, const Slice* end) override;
   void AppendTS(const Slice& val, std::string* val_with_ts,uint64_t ttl);
+  static uint64_t GetTS(const std::string* val);
   // Extra methods (for testing) that are not in the public DB interface
 
   // Compact any files in the named level that overlap [*begin,*end]
diff --git a/db/memtable.cc b/db/memtable.cc
index 6b875e0..c93aff9 100644
--- a/db/memtable.cc
+++ b/db/memtable.cc
@@ -100,6 +100,13 @@ void MemTable::Add(SequenceNumber s, ValueType type, const Slice& key,
   table_.Insert(buf);
 }
 
+/**
+ * @descrption: ttl问题场景：一个key，多个版本，其ttl的相对大小于版本号的相对大小不同
+ * @param key
+ * @param value
+ * @param s
+ * @return
+ */
 bool MemTable::Get(const LookupKey& key, std::string* value, Status* s) {
   Slice memkey = key.memtable_key();
   Table::Iterator iter(&table_);
diff --git a/include/leveldb/db.h b/include/leveldb/db.h
index 481f43b..9f48b29 100644
--- a/include/leveldb/db.h
+++ b/include/leveldb/db.h
@@ -152,6 +152,8 @@ class LEVELDB_EXPORT DB {
                      const Slice& value, uint64_t ttl) = 0;
 //  virtual Status Write(const WriteOptions& options, WriteBatch* updates,uint64_t ttl) = 0;
 
+//  virtual void AppendTS(const Slice& val, std::string* val_with_ts,uint64_t ttl) = 0;
+//  virtual void AppendTS(const Slice& val, std::string* val_with_ts,uint64_t ttl) = 0;
 };
 
 // Destroy the contents of the specified database.
diff --git a/include/leveldb/status.h b/include/leveldb/status.h
index e327314..e4943be 100644
--- a/include/leveldb/status.h
+++ b/include/leveldb/status.h
@@ -52,6 +52,9 @@ class LEVELDB_EXPORT Status {
   static Status IOError(const Slice& msg, const Slice& msg2 = Slice()) {
     return Status(kIOError, msg, msg2);
   }
+  static Status Expire(const Slice& msg, const Slice& msg2 = Slice()) {
+    return Status(kExpire, msg, msg2);
+  }
 
   // Returns true iff the status indicates success.
   bool ok() const { return (state_ == nullptr); }
@@ -82,7 +85,8 @@ class LEVELDB_EXPORT Status {
     kCorruption = 2,
     kNotSupported = 3,
     kInvalidArgument = 4,
-    kIOError = 5
+    kIOError = 5,
+    kExpire = 6
   };
 
   Code code() const {
diff --git a/test/db_test2.cc b/test/db_test2.cc
index 76fd0ba..36ed8f6 100644
--- a/test/db_test2.cc
+++ b/test/db_test2.cc
@@ -1,14 +1,21 @@
 #include "leveldb/db.h"
 #include "leveldb/filter_policy.h"
 
+#include "leveldb/env.h"
+#include "leveldb/db.h"
+
+
+using namespace leveldb;
+
+constexpr int value_size = 2048;
+constexpr int data_size = 128 << 20;
+
 #include <iostream>
 #include <cstdlib>
 #include <ctime>
 
 using namespace leveldb;
 
-constexpr int value_size = 2048;
-constexpr int data_size = 256 << 20;
 
 // 3. 数据管理（Manifest/创建/恢复数据库）
 Status OpenDB(std::string dbName, DB **db) {
@@ -40,9 +47,12 @@ void InsertData(DB *db, uint64_t ttl/* second */) {
 
   for (int i = 0; i < key_num; i++) {
     int key_ = rand() % key_num+1;
+    key_ = 1;
     std::string key = std::to_string(key_);
     std::string value(value_size, 'a');
     db->Put(writeOptions, key, value, ttl);
+    std::cout << "time to alive" << ttl << std::endl;
+    break;
   }
 }
 // 2. 数据访问（如何读数据）
@@ -54,9 +64,11 @@ void GetData(DB *db, int size = (1 << 30)) {
   srand(static_cast<unsigned int>(time(0)));
   for (int i = 0; i < 100; i++) {
     int key_ = rand() % key_num+1;
+
     std::string key = std::to_string(key_);
     std::string value;
     db->Get(readOptions, key, &value);
+    //break;
   }
 
   // 范围查询
@@ -70,19 +82,54 @@ void GetData(DB *db, int size = (1 << 30)) {
 
 int main() {
 
+//  DB *db;
+//  if(OpenDB("testdb", &db).ok()) {
+//    uint64_t ttl = 20;
+//
+//    InsertData(db, ttl);
+//    delete db;
+//  }
+//
+//  if(OpenDB("testdb", &db).ok()) {
+//    GetData(db);
+//    delete db;
+//  }
+//
   DB *db;
-  if(OpenDB("testdb", &db).ok()) {
-    uint64_t ttl = 20;
+  if(OpenDB("testdb", &db).ok() == false) {
+    std::cerr << "open db failed" << std::endl;
+    abort();
+  }
 
-    InsertData(db, ttl);
-    delete db;
+  uint64_t ttl = 200;
+
+  InsertData(db, ttl);
+
+  ReadOptions readOptions;
+  Status status;
+  int key_num = data_size / value_size;
+  srand(static_cast<unsigned int>(time(0)));
+  for (int i = 0; i < 100; i++) {
+    int key_ = rand() % key_num+1;
+    key_ = 1;
+    std::string key = std::to_string(key_);
+    std::string value;
+    status = db->Get(readOptions, key, &value);
+    assert(status.ok());
+    break;
   }
 
-  if(OpenDB("testdb", &db).ok()) {
-    GetData(db);
-    delete db;
+  Env::Default()->SleepForMicroseconds(ttl * 10000);
+
+  for (int i = 0; i < 100; i++) {
+    int key_ = rand() % key_num+1;
+    key_ = 1;
+    std::string key = std::to_string(key_);
+    std::string value;
+    status = db->Get(readOptions, key, &value);
+    assert(status.ok() != true);
+    break;
   }
-  
   return 0;
 }
 
diff --git a/test/simple_test.cc b/test/simple_test.cc
new file mode 100644
index 0000000..a4e5f3c
--- /dev/null
+++ b/test/simple_test.cc
@@ -0,0 +1,93 @@
+#include "leveldb/db.h"
+#include "leveldb/filter_policy.h"
+
+#include "leveldb/env.h"
+#include "leveldb/db.h"
+
+
+using namespace leveldb;
+
+constexpr int value_size = 2048;
+constexpr int data_size = 128 << 20;
+
+#include <iostream>
+#include <cstdlib>
+#include <ctime>
+
+using namespace leveldb;
+
+
+// 3. 数据管理（Manifest/创建/恢复数据库）
+Status OpenDB(std::string dbName, DB **db) {
+  Options options;
+  options.create_if_missing = true;
+  options.filter_policy = NewBloomFilterPolicy(10);
+  return DB::Open(options, dbName, db);
+}
+
+// 1. 存储（数据结构与写入）
+// 4. 数据合并（Compaction）
+//void InsertData(DB *db) {
+//  WriteOptions writeOptions;
+//  int key_num = data_size / value_size;
+//  srand(static_cast<unsigned int>(time(0)));
+//
+//  for (int i = 0; i < key_num; i++) {
+//    int key_ = rand() % key_num+1;
+//    std::string key = std::to_string(key_);
+//    std::string value(value_size, 'a');
+//    db->Put(writeOptions, key, value);
+//  }
+//}
+
+void InsertData(DB *db, uint64_t ttl/* second */) {
+  WriteOptions writeOptions;
+  int key_num = data_size / value_size;
+  srand(static_cast<unsigned int>(time(0)));
+  for (int i = 0; i < key_num; i++) {
+    int key_ = rand() % key_num+1;
+    key_ = 1;
+    std::string key = std::to_string(key_);
+    std::string value(value_size, 'a');
+    db->Put(writeOptions, key, value, ttl);
+    std::cout << "time to alive" << ttl << std::endl;
+    break;
+  }
+}
+
+int main() {
+
+  DB *db;
+  if(OpenDB("testdb", &db).ok() == false) {
+    std::cerr << "open db failed" << std::endl;
+    abort();
+  }
+
+  uint64_t ttl = 200;
+
+//  InsertData(db, ttl);
+  WriteOptions writeOptions;
+  int key_ = 1;
+  std::string key = std::to_string(key_);
+  std::string value(1, 'a');
+  db->Put(writeOptions, key, value, ttl);
+  std::cout << "time to alive" << ttl << std::endl;
+
+  ReadOptions readOptions;
+  std::string value_read;
+  Status status = db->Get(readOptions, key, &value);
+
+
+  //std::cout<<"start sleep for " <<
+  Env::Default()->SleepForMicroseconds(ttl * 100000);
+
+
+  key_ = 1;
+  key = std::to_string(key_);
+  std::string value_read_second;
+  status = db->Get(readOptions, key, &value_read_second);
+  assert(status.ok() != true);
+
+  return 0;
+}
+