methods for addition with overwrite

cache.h

@@ -39,6 +39,7 @@ private:
 
 public:
     virtual void addRecord(const K& key, const V& value) override;
+    virtual bool forceRecord(const K& key, const V& value) override;
     virtual void changeRecord(const K& key, const V& value) override;
     virtual void removeRecord(const K& key) override;
     virtual V getRecord(const K& key) const override;

cache.hpp

@@ -52,8 +52,35 @@ void DataBase::Cache<K, V>::addRecord(const K& key, const V& value) {
 
     Table<K, V>::addRecord(key, value);
     cache->insert(std::make_pair(key, value));
+
+    if (*mode != Mode::full) {
+        abscent->erase(key);
+    }
 }
 
+template<class K, class V>
+bool DataBase::Cache<K, V>::forceRecord(const K& key, const V& value) {
+    if (!DataBase::Table<K, V>::db->opened) {
+        throw Closed("forceRecord", DataBase::Table<K, V>::db->name, DataBase::Table<K, V>::name);
+    }
+
+    bool added = Table<K, V>::forceRecord(key, value);
+    if (*mode == Mode::full) {
+        (*cache)[key] = value;
+    } else {
+        if (added) {
+            abscent->erase(key);
+        }
+        std::pair<typename std::map<K, V>::iterator, bool> result = cache->insert(std::make_pair(key, value));
+        if (!result.second) {
+            result.first->second = value;
+        } else if (!added) {        //this way database had value but cache didn't, so, need to decrease sizeDifference
+            handleMode();
+        }
+    }
+
+    return added;
+}
 
 template<class K, class V>
 void DataBase::Cache<K, V>::changeRecord(const K& key, const V& value) {

table.h

@@ -55,6 +55,7 @@ protected:
 
 public:
     virtual void addRecord(const K& key, const V& value);
+    virtual bool forceRecord(const K& key, const V& value);     //returns true if there was addition, false if change
     virtual void changeRecord(const K& key, const V& value);
     virtual void removeRecord(const K& key);
     virtual V getRecord(const K& key) const;

table.hpp

@@ -58,7 +58,38 @@ void DataBase::Table<K, V>::addRecord(const K& key, const V& value) {
     }
 }
 
+template<class K, class V>
+bool DataBase::Table<K, V>::forceRecord(const K& key, const V& value) {
+    if (!db->opened) {
+        throw Closed("forceRecord", db->name, name);
+    }
 
+    bool added;
+    MDB_val lmdbKey = keySerializer->setData(key);
+    MDB_val lmdbData;
+    MDB_txn *txn;
+    mdb_txn_begin(db->environment, NULL, 0, &txn);
+    int rc;
+    rc = mdb_get(txn, dbi, &lmdbKey, &lmdbData);
+    if (rc == 0) {
+        added = false;
+    } else if (rc == MDB_NOTFOUND) {
+        added = true;
+    } else {
+        mdb_txn_abort(txn);
+        throw Unknown(db->name, mdb_strerror(rc), name);
+    }
+    lmdbData = valueSerializer->setData(value);
+    rc = mdb_put(txn, dbi, &lmdbKey, &lmdbData, 0);
+    if (rc != 0) {
+        mdb_txn_abort(txn);
+        throw Unknown(db->name, mdb_strerror(rc), name);
+    } else {
+        mdb_txn_commit(txn);
+    }
+
+    return added;
+}
 
 template<class K, class V>
 void DataBase::Table<K, V>::changeRecord(const K& key, const V& value) {