diff --git a/3DB设计.md b/3DB设计.md
index 3e155a0..b37079f 100644
--- a/3DB设计.md
+++ b/3DB设计.md
@@ -59,6 +59,13 @@ indexDB的写入情况判断如下：扫描indexDB，如果是creating操作且
 
 当然，这些处理的方式会比较的细，总的来讲，只要kvDB完成写入，那么indexDB就可以完成更新；如果写入未完成，那么indexDB就需要用某种方式回滚。
 
+# 全写入方案
+不用时间戳，全部写入metaDB作为log，然后再写入kvDB和indexDB
+
+# 整体架构
+采用多线程架构
+由于二级索引理论上是幂等的操作,所以或许不用taskqueue来阻塞创建之后的写入？
+如果这么看的话，其实创建（删除）索引的操作也不需要
 
 
 
diff --git a/fielddb/field_db.cpp b/fielddb/field_db.cpp
index 1de6565..5d28813 100644
--- a/fielddb/field_db.cpp
+++ b/fielddb/field_db.cpp
@@ -1,5 +1,6 @@
 #include "fielddb/field_db.h"
 #include <cstdint>
+#include <string>
 #include <vector>
 #include "leveldb/db.h"
 #include "leveldb/env.h"
@@ -7,13 +8,31 @@
 #include "leveldb/status.h"
 #include "util/serialize_value.h"
 
-namespace leveldb {
+namespace fielddb {
+using namespace leveldb;
 //TODO:打开fieldDB
-static Status OpenFieldDB(const Options& options,const std::string& name,DB** dbptr) {
+Status FieldDB::OpenFieldDB(const Options& options,const std::string& name,DB** dbptr) {
     // options.env->CreateDir("./abc")
+    *dbptr = new FieldDB(options,name);
     return Status::OK();
 }
 
+Status FieldDB::Recover() {
+    
+}
+
+FieldDB::FieldDB(const Options& options,const std::string& name) {
+    Status status;
+    status = Open(options, name+"_indexDB", &indexDB);
+    if(!status.ok()) return;
+    status = Open(options, name+"_kvDB", &kvDB);
+    if(!status.ok()) return;
+    status = Open(options, name+"_metaDB", &metaDB);
+    if(!status.ok()) return;
+    
+    Recover();
+}
+
 
 Status FieldDB::Put(const WriteOptions &options, const Slice &key, const Slice &value) {
     return kvDB->Put(options, key, value);
diff --git a/fielddb/field_db.h b/fielddb/field_db.h
index 23534aa..411f564 100644
--- a/fielddb/field_db.h
+++ b/fielddb/field_db.h
@@ -1,10 +1,21 @@
 #include "db/db_impl.h"
+#include <deque>
+#include <map>
+#include <set>
+#include <string>
 #include "leveldb/db.h"
 #include "leveldb/options.h"
+#include "leveldb/slice.h"
 #include "leveldb/status.h"
-namespace leveldb{
-class FieldDB:leveldb::DB {
+#include "port/port_stdcxx.h"
+#include "fielddb/request.h"
+
+namespace fielddb {
+using namespace leveldb;
+class FieldDB : leveldb::DB {
 public:
+    FieldDB() = default;
+    FieldDB(const Options& options,const std::string& name);
 /*lab1的要求*/
     Status Put(const WriteOptions &options, const Slice &key, const Slice &value) override;
     Status PutFields(const WriteOptions &, const Slice &key, const FieldArray &fields) override;
@@ -24,10 +35,25 @@ public:
     bool DeleteIndex(std::string &field_name);
     std::vector<std::string> QueryByIndex(Field &field);
 
-private:
     static Status OpenFieldDB(const Options& options,const std::string& name,DB** dbptr);
 
-    leveldb::DBImpl *indexDB;
-    leveldb::DBImpl *kvDB;
+private:
+    //根据metaDB的内容进行恢复
+    Status Recover(); 
+
+private:
+    leveldb::DB *metaDB;
+    leveldb::DB *indexDB;
+    leveldb::DB *kvDB;
+
+    enum IndexStatus{
+        Creating,
+        Deleting,
+        Exist
+    };
+    std::map<std::string,int> index;
+    port::Mutex _mutex; // mutex for taskqueue
+    std::deque<Request *> taskqueue;
+
 };
 } // end of namespace
\ No newline at end of file
diff --git a/fielddb/metakv.cpp b/fielddb/metakv.cpp
new file mode 100644
index 0000000..819030f
--- /dev/null
+++ b/fielddb/metakv.cpp
@@ -0,0 +1,20 @@
+#include "fielddb/metakv.h"
+#include "util/coding.h"
+#include <string>
+
+namespace fielddb {
+using namespace leveldb;
+
+Slice MetaKV::metaKey() {
+    std::string buf;
+    PutLengthPrefixedSlice(&buf, Key);
+    PutFixed64(&buf, meta_seq);
+    PutFixed32(&buf, tag);
+    return Slice(buf);
+}
+
+Slice MetaKV::metaValue() {
+    return Slice(SerializeValue(Fields));
+}
+
+}
\ No newline at end of file
diff --git a/fielddb/metakv.h b/fielddb/metakv.h
new file mode 100644
index 0000000..f976830
--- /dev/null
+++ b/fielddb/metakv.h
@@ -0,0 +1,26 @@
+#pragma once
+
+#include <cstdint>
+#include <cstdio>
+#include "leveldb/slice.h"
+#include "util/serialize_value.h"
+namespace fielddb {
+using namespace leveldb;
+/*根据写入的流程可以推断，需要存在metaDB中的数据其实都是带索引的数据,也就是FieldArray*/
+class MetaKV {
+    MetaKV(Slice &Key,FieldArray Fields):
+        Key(Key),Fields(Fields),tag(0),meta_seq(0) { }
+    inline int get_seq() { return meta_seq; }
+    inline void set_seq(int meta_seq) { this->meta_seq = meta_seq; }
+    inline void setPut() { tag = PUT; }
+    inline void setDelete() { tag = DELETE; }
+    Slice metaKey();
+    Slice metaValue();
+private:
+    enum {PUT = 0x0,DELETE = 0x1};
+    uint64_t meta_seq;
+    uint8_t tag;
+    Slice &Key;
+    FieldArray Fields;
+};
+}
\ No newline at end of file
diff --git a/fielddb/request.cpp b/fielddb/request.cpp
new file mode 100644
index 0000000..e69de29
diff --git a/fielddb/request.h b/fielddb/request.h
new file mode 100644
index 0000000..3831fed
--- /dev/null
+++ b/fielddb/request.h
@@ -0,0 +1,25 @@
+#include <string>
+#include "port/port_stdcxx.h"
+#include "util/mutexlock.h"
+#include "util/serialize_value.h"
+namespace fielddb {
+using namespace leveldb;
+// 在taskqueue中的Request，由taskqueue最开始的线程处理一批Request
+// 这个思路与write写入的思路类似
+class Request {
+public:
+    Request(std::string *Key,std::string *Value,port::Mutex *mu):
+        Key(Key),Value(Value),hasFields(false),_cond(mu) { }
+    Request(std::string *Key,FieldArray *Fields,port::Mutex *mu):
+        Key(Key),Fields(Fields),hasFields(false),_cond(mu) { }
+
+private:
+    bool done;
+    port::CondVar _cond;
+
+    bool hasFields;
+    std::string *Key;
+    std::string *Value;
+    FieldArray *Fields;
+};
+}
\ No newline at end of file