feat(db): add count api

Former-commit-id: 9fb2b765a48d1753ba31a68e7b9b207273adb199

cpp/src/db/DB.h

@@ -32,6 +32,8 @@ public:
 
     virtual Status drop_all() = 0;
 
+    virtual Status count(const std::string& group_id, long& result) = 0;
+
     DB() = default;
     DB(const DB&) = delete;
     DB& operator=(const DB&) = delete;

cpp/src/db/DBImpl.cpp

@@ -348,6 +348,10 @@ Status DBImpl::drop_all() {
     return _pMeta->drop_all();
 }
 
+Status DBImpl::count(const std::string& group_id, long& result) {
+    return _pMeta->count(group_id, result);
+}
+
 DBImpl::~DBImpl() {
     {
         std::unique_lock<std::mutex> lock(_mutex);

cpp/src/db/DBImpl.h

@@ -38,6 +38,8 @@ public:
 
     virtual Status drop_all() override;
 
+    virtual Status count(const std::string& group_id, long& result) override;
+
     virtual ~DBImpl();
 
 private:

cpp/src/db/DBMetaImpl.cpp

@@ -427,6 +427,31 @@ Status DBMetaImpl::cleanup() {
     return Status::OK();
 }
 
+Status DBMetaImpl::count(const std::string& group_id, long& result) {
+
+    auto selected = ConnectorPtr->select(columns(&GroupFileSchema::rows,
+                                               &GroupFileSchema::date),
+                                      where((c(&GroupFileSchema::file_type) == (int)GroupFileSchema::RAW or
+                                             c(&GroupFileSchema::file_type) == (int)GroupFileSchema::TO_INDEX or
+                                             c(&GroupFileSchema::file_type) == (int)GroupFileSchema::INDEX) and
+                                            c(&GroupFileSchema::group_id) == group_id));
+
+    GroupSchema group_info;
+    group_info.group_id = group_id;
+    auto status = get_group_no_lock(group_info);
+    if (!status.ok()) {
+        return status;
+    }
+
+    result = 0;
+    for (auto& file : selected) {
+        result += std::get<0>(file);
+    }
+
+    result /= group_info.dimension;
+    return Status::OK();
+}
+
 Status DBMetaImpl::drop_all() {
     if (boost::filesystem::is_directory(_options.path)) {
         boost::filesystem::remove_all(_options.path);

cpp/src/db/DBMetaImpl.h

@@ -50,6 +50,8 @@ public:
 
     virtual Status drop_all() override;
 
+    virtual Status count(const std::string& group_id, long& result) override;
+
     virtual ~DBMetaImpl();
 
 private:

cpp/src/db/LocalMetaImpl.cpp

@@ -251,6 +251,11 @@ Status LocalMetaImpl::drop_all() {
     return Status::OK();
 }
 
+Status LocalMetaImpl::count(const std::string& group_id, long& result) {
+    // PXU TODO
+    return Status::OK();
+}
+
 } // namespace meta
 } // namespace engine
 } // namespace vecwise

cpp/src/db/LocalMetaImpl.h

@@ -43,6 +43,8 @@ public:
 
     virtual Status cleanup_ttl_files(uint16_t seconds) override;
 
+    virtual Status count(const std::string& group_id, long& result) override;
+
     virtual Status drop_all() override;
 
 private:

cpp/src/db/Meta.h

@@ -85,6 +85,8 @@ public:
 
     virtual Status drop_all() = 0;
 
+    virtual Status count(const std::string& group_id, long& result) = 0;
+
     static DateT GetDate(const std::time_t& t);
     static DateT GetDate();
 

cpp/unittest/db/db_tests.cpp

@@ -66,7 +66,7 @@ TEST(DBTest, DB_TEST) {
         qxb[d * i] += i / 2000.;
     }
 
-    int loop = 500000;
+    int loop = 50000;
 
     for (auto i=0; i<loop; ++i) {
         if (i==40) {
@@ -78,6 +78,10 @@ TEST(DBTest, DB_TEST) {
 
     std::this_thread::sleep_for(std::chrono::seconds(2));
 
+    long count = 0;
+    db->count(group_name, count);
+    LOG(DEBUG) << "Count=" << count;
+
     engine::QueryResults results;
     int k = 10;
     LOG(DEBUG) << "PRE";