diff --git a/cpp/src/db.h b/cpp/src/db.h
index 5d8c0cf791dcf1353a15e0df506006e6e4bf2316..1840450502a1519a43e75d73eb5dac56e3b37491 100644
--- a/cpp/src/db.h
+++ b/cpp/src/db.h
@@ -1,6 +1,7 @@
 #ifndef VECENGINE_DB_H_
 #define VECENGINE_DB_H_
 
+#include <string>
 #include "options.h"
 
 namespace vecengine {
@@ -11,6 +12,9 @@ class DB {
 public:
     static DB* Open(const Options& options_, const std::string& name_);
 
+    virtual std::string add_group(GroupOptions options_,
+            const std::string& group_id_) = 0;
+
     DB() = default;
     DB(const DB&) = delete;
     DB& operator=(const DB&) = delete;
diff --git a/cpp/src/db_impl.cpp b/cpp/src/db_impl.cpp
index 66ee9633ee49eb59a6c26f9741b0162e5907e0d2..3d030d9e2aedcad95c21543bb1afc61d2086ba60 100644
--- a/cpp/src/db_impl.cpp
+++ b/cpp/src/db_impl.cpp
@@ -1,11 +1,31 @@
-include "db_impl.h"
+#include <assert.h>
+#include "db_impl.h"
 
 namespace vecengine {
 
-DB::DB(const Options& options_, const std::string& name_)
+DBImpl::DBImpl(const Options& options_, const std::string& name_)
     : _dbname(name_),
       _env(options_.env),
       _options(options_) {
 }
 
+Status DBImpl::add_group(const GroupOptions& options_,
+        const std::string& group_id_,
+        std::string& gid_) {
+    assert((!options_.has_id) ||
+            (options_.has_id && ("" != group_id_)));
+
+}
+
+/*
+ *  DB
+ */
+
+DB::~DB() {}
+
+DB* DB::Open(const Options& options_, const std::string& name_) {
+    DBImpl* impl = new DBImpl(options_, name_);
+    return impl;
+}
+
 } // namespace vecengine
diff --git a/cpp/src/db_impl.h b/cpp/src/db_impl.h
index 7dc55273f111c36559f8bb4479477f53abdeebf8..0d7d2a3f10a7567a43d9b965456cd123459e2fa9 100644
--- a/cpp/src/db_impl.h
+++ b/cpp/src/db_impl.h
@@ -11,8 +11,16 @@ class DBImpl : public DB {
 public:
     DBImpl(const Options& options_, const std::string& name_);
 
+    virtual Status add_group(GroupOptions options_,
+            const std::string& group_id_,
+            std::string& gid_) override;
+
     virtual ~DBImpl();
 private:
+
+    Status meta_add_group(const std::string& group_id_);
+    Status meta_add_group_file(const std::string& group_id_);
+
     const _dbname;
     Env* const _env;
     const Options _options;
diff --git a/cpp/src/db_meta.cpp b/cpp/src/db_meta.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..c1fc0f75f25342880ebeeda79c36d19ef29f563f
--- /dev/null
+++ b/cpp/src/db_meta.cpp
@@ -0,0 +1,14 @@
+#include "db_meta.h"
+
+namespace zilliz {
+namespace vecwise {
+namespace engine {
+
+Meta* Meta::Default() {
+    static DefaultMeta meta;
+    return *meta;
+}
+
+} // namespace engine
+} // namespace vecwise
+} // namespace zilliz
diff --git a/cpp/src/db_meta.h b/cpp/src/db_meta.h
new file mode 100644
index 0000000000000000000000000000000000000000..e84d97051fef123b8265115565deab95fcf8214d
--- /dev/null
+++ b/cpp/src/db_meta.h
@@ -0,0 +1,60 @@
+#ifndef VECENGINE_DB_META_H_
+#define VECENGINE_DB_META_H_
+
+namespace zilliz {
+namespace vecwise {
+namespace engine {
+
+struct GroupSchema {
+    size_t id;
+    std::string group_id;
+    size_t files_cnt = 0;
+    uint16_t dimension;
+    std::string location = "";
+}; // GroupSchema
+
+
+struct GroupFileSchema {
+    typedef enum {
+        RAW,
+        INDEX
+    } FILE_TYPE;
+
+    size_t id;
+    std::string group_id;
+    std::string file_id;
+    int files_type = RAW;
+    size_t rows;
+    std::string location = "";
+}; // GroupFileSchema
+
+typedef std::vector<GroupFileSchema> GroupFilesSchema;
+
+
+class Meta {
+public:
+    virtual Status add_group(const std::string& group_id_, GroupSchema& group_info) = 0;
+    virtual Status get_group(const std::string& group_id_, GroupSchema& group_info) = 0;
+    virtual Status has_group(const std::string& group_id_, bool& has_or_not) = 0;
+
+    virtual Status add_group_file(const std::string& group_id,
+                                  GroupFileSchema& group_file_info) = 0;
+    virtual Status has_group_file(const std::string& group_id,
+                                  const std::string& file_id,
+                                  bool& has_or_not) = 0;
+    virtual Status get_group_file(const std::string& group_id,
+                                  const std::string& file_id,
+                                  GroupFileSchema& group_file_info) = 0;
+    virtual Status mark_group_file_as_index(const std::string& group_id,
+                                            const std::string& file_id) = 0;
+
+    virtual Status get_group_files(const std::string& group_id,
+                                   GroupFilesSchema& group_files_info) = 0;
+
+}; // MetaData
+
+} // namespace engine
+} // namespace vecwise
+} // namespace zilliz
+
+#endif // VECENGINE_DB_META_H_
diff --git a/cpp/src/db_meta_impl.cpp b/cpp/src/db_meta_impl.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..a6754a817dc7925ff1e3a278a8291b5a47461445
--- /dev/null
+++ b/cpp/src/db_meta_impl.cpp
@@ -0,0 +1,66 @@
+#include "db_meta_impl.h"
+
+namespace zilliz {
+namespace vecwise {
+namespace engine {
+
+Status DBMetaImpl::DBMetaImpl(DBMetaOptions options_)
+    : _options(options_) {
+    initialize();
+}
+
+Status DBMetaImpl::initialize() {
+    // PXU TODO: Create DB Connection
+    return Status.OK();
+}
+
+Status DBMetaImpl::add_group(const std::string& group_id_, GroupSchema& group_info) {
+    //PXU TODO
+    return Status.OK();
+}
+
+Status DBMetaImpl::get_group(const std::string& group_id_, GroupSchema& group_info) {
+    //PXU TODO
+    return Status.OK();
+}
+
+Status DBMetaImpl::has_group(const std::string& group_id_, bool& has_or_not) {
+    //PXU TODO
+    return Status.OK();
+}
+
+Status DBMetaImpl::add_group_file(const std::string& group_id,
+                              GroupFileSchema& group_file_info) {
+    //PXU TODO
+    return Status.OK();
+}
+
+Status DBMetaImpl::has_group_file(const std::string& group_id,
+                              const std::string& file_id,
+                              bool& has_or_not) {
+    //PXU TODO
+    return Status.OK();
+}
+
+Status DBMetaImpl::get_group_file(const std::string& group_id,
+                              const std::string& file_id,
+                              GroupFileSchema& group_file_info) {
+    //PXU TODO
+    return Status.OK();
+}
+
+Status DBMetaImpl::get_group_files(const std::string& group_id,
+                               GroupFilesSchema& group_files_info) {
+    // PXU TODO
+    return Status.OK();
+}
+
+Status DBMetaImpl::mark_group_file_as_index(const std::string& group_id,
+                                        const std::string& file_id) {
+    //PXU TODO
+    return Status.OK();
+}
+
+} // namespace engine
+} // namespace vecwise
+} // namespace zilliz
diff --git a/cpp/src/db_meta_impl.h b/cpp/src/db_meta_impl.h
new file mode 100644
index 0000000000000000000000000000000000000000..d3aa5e19d634fd57fa310a9c6aa7a103ceee093a
--- /dev/null
+++ b/cpp/src/db_meta_impl.h
@@ -0,0 +1,45 @@
+#ifndef VECENGINE_DB_META_IMPL_H_
+#define VECENGINE_DB_META_IMPL_H_
+
+#include "db_meta.h"
+#include "options.h"
+
+namespace zilliz {
+namespace vecwise {
+namespace engine {
+
+class DBMetaImpl : public Meta {
+public:
+    DBMetaImpl(DBMetaOptions& options_);
+
+    virtual Status add_group(const std::string& group_id_, GroupSchema& group_info) override;
+    virtual Status get_group(const std::string& group_id_, GroupSchema& group_info) override;
+    virtual Status has_group(const std::string& group_id_, bool& has_or_not) override;
+
+    virtual Status add_group_file(const std::string& group_id,
+                                  GroupFileSchema& group_file_info) override;
+    virtual Status has_group_file(const std::string& group_id,
+                                  const std::string& file_id,
+                                  bool& has_or_not) override;
+    virtual Status get_group_file(const std::string& group_id,
+                                  const std::string& file_id,
+                                  GroupFileSchema& group_file_info) override;
+    virtual Status mark_group_file_as_index(const std::string& group_id,
+                                            const std::string& file_id) override;
+
+    virtual Status get_group_files(const std::string& group_id,
+                                   GroupFilesSchema& group_files_info) override;
+
+private:
+
+    Status initialize();
+
+    const DBMetaOptions _options;
+
+}; // DBMetaImpl
+
+} // namespace engine
+} // namespace vecwise
+} // namespace zilliz
+
+#endif // VECENGINE_DB_META_IMPL_H_
diff --git a/cpp/src/options.h b/cpp/src/options.h
index 114861104ddd99aceee36b429ff71b01ec896288..f07f10cd39438c78dc1fd6fa650750e5ce7e63fc 100644
--- a/cpp/src/options.h
+++ b/cpp/src/options.h
@@ -1,12 +1,30 @@
 #ifndef VECENGINE_OPTIONS_H_
 #define VECENGINE_OPTIONS_H_
 
+#include <string>
+
 namespace vecengine {
 
 struct Options {
 
 }; // Options
 
+
+struct GroupOptions {
+    size_t dimension;
+    bool has_id = false;
+}; // GroupOptions
+
+
+struct MetaOptions {
+}; // MetaOptions
+
+
+struct DBMetaOptions : public MetaOptions {
+    std::string db_uri;
+}; // DBMetaOptions
+
+
 } // namespace vecengine
 
 #endif // VECENGINE_OPTIONS_H_
diff --git a/cpp/src/status.cpp b/cpp/src/status.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..8c547d5abec0be84885e33c6cdfb88a5b96f81d6
--- /dev/null
+++ b/cpp/src/status.cpp
@@ -0,0 +1,52 @@
+#include "status.h"
+
+namespace vecengine {
+
+const char* Status::CopyState(const char* state_) {
+    uint32_t size;
+    memcpy(&size, state_, sizeof(size));
+    char result = new char[size+5];
+    memcpy(result, state_, size+5);
+    return result;
+}
+
+Status::Status(Code code_, const std::string& msg_, const std::string& msg2_) {
+    assert(code_ != kOK);
+    const uint32_t len1 = msg_.size();
+    const uint32_t len2 = msg2_.size();
+    const uint32_t size = len1 + (len2 ? (2+len2) : 0);
+    char* result = new char[size+5];
+    memcpy(result, &size, sizeof(size));
+    result[4] = static_cast<char>(code);
+    memcpy(result+5, msg_.data(), len1);
+    if (len2) {
+        result[5 + len1] = ':';
+        result[6 + len1] = ' ';
+        memcpy(result + 7 + len1, msg2_.data(), len2);
+    }
+    _state = result;
+}
+
+std::string Status::ToString() const {
+    if (_state == nullptr) return "OK";
+    char tmp[30];
+    const char* type;
+    switch (code()) {
+        case kOK:
+            type = "OK";
+            break;
+        default:
+            snprintf(tmp, sizeof(tmp), "Unkown code(%d): ",
+                    static_cast<int>(code()));
+            type = tmp;
+            break;
+    }
+
+    std::string result(type);
+    uint32_t length;
+    memcpy(&length, state_, sizeof(length));
+    result.append(state_ + 5, length);
+    return result;
+}
+
+} // namespace vecengine
diff --git a/cpp/src/status.h b/cpp/src/status.h
new file mode 100644
index 0000000000000000000000000000000000000000..01e3a4ce5dc1da6619e441ac81e71ab9e135e6c9
--- /dev/null
+++ b/cpp/src/status.h
@@ -0,0 +1,55 @@
+#ifndef VECENGINE_STATUS_H_
+#define VECENGINE_STATUS_H_
+
+namespace vecengine {
+
+class Status {
+public:
+    Status() noexcept : _state(nullptr) {}
+    ~Status() { delete[] _state; }
+
+    Status(const Status& rhs_);
+    Status& operator=(const Status& rhs_);
+
+    Status(const Status&& rhs_) noexcept : _state(rhs_._state) { rhs_._state = nullptr; }
+    Status& operator=(const Status& rhs_) noexcept;
+
+    static Status OK() { return Status(); }
+
+    bool ok() const { return _state == nullptr; }
+
+private:
+    const char* _state;
+
+    enum Code {
+        kOK = 0,
+    };
+
+    Code code() const {
+        return (_state == nullptr) ? kOK : static_cast<Code>(_state[4])
+    }
+
+    static const char* CopyState(const char* s);
+
+}; // Status
+
+inline Status::Status(const Status* rhs_) {
+    _state = (rhs_._state == nullptr) ? nullptr : CopyState(rhs_._state);
+}
+
+inline Status& Status::operator=(const Status& rhs_) {
+    if (_state != rhs_._state) {
+        delete[] state_;
+        _state = (rhs_._state == nullptr) ? nullptr : CopyState(rhs_._state);
+    }
+    return *this;
+}
+
+inline Status& Status::operator=(Status&& rhs_) noexcept {
+    std::swap(_state, rhs_._state);
+    return *this;
+}
+
+} // namespace vecengine
+
+#endif // VECENGINE_STATUS_H_