diff --git a/src/colnod/databasemanager.cpp b/src/colnod/databasemanager.cpp
index eba3f10..e2a6059 100644
--- a/src/colnod/databasemanager.cpp
+++ b/src/colnod/databasemanager.cpp
@@ -16,7 +16,7 @@ DatabaseManager::DatabaseManager(const QString& host, const QString& dbName, con
 }
 
 // add or update subject to db
-int DatabaseManager::saveSubject(std::shared_ptr<Subject> subject, const QString& table)
+int DatabaseManager::saveSubject(const std::shared_ptr<Subject>& subject, const QString& table)
 {
     QSqlQuery query;
     QString id = subject->idToStringWithoutBraces();
@@ -42,7 +42,7 @@ int DatabaseManager::saveSubject(std::shared_ptr<Subject> subject, const QString
 }
 
 // add or update token to DB
-int DatabaseManager::saveToken(std::shared_ptr<Token> token, const QString& table)
+int DatabaseManager::saveToken(const std::shared_ptr<Token>& token, const QString& table)
 {
     QSqlQuery query;
     QString id = token->idToStringWithoutBraces();
@@ -75,7 +75,7 @@ int DatabaseManager::saveToken(std::shared_ptr<Token> token, const QString& tabl
 }
 
 // add of update subject attributes
-void DatabaseManager::saveSubjectAttributes(std::shared_ptr<Subject> subject, const QString& table)
+void DatabaseManager::saveSubjectAttributes(const std::shared_ptr<Subject>& subject, const QString& table)
 {
     QSqlQuery query;
     auto attributes = subject->getAtr();
diff --git a/src/colnod/databasemanager.h b/src/colnod/databasemanager.h
index 3d3fef6..1ce4b50 100644
--- a/src/colnod/databasemanager.h
+++ b/src/colnod/databasemanager.h
@@ -19,9 +19,9 @@ class DatabaseManager : public QObject
 public:
     DatabaseManager(const QString& host, const QString& dbName, const QString& user, const QString& password, const bool& dryMode = false);
 
-    int saveSubject(std::shared_ptr<Subject> subject, const QString& table);
-    int saveToken(std::shared_ptr<Token> token, const QString& table);
-    void saveSubjectAttributes(std::shared_ptr<Subject> subject, const QString& table);
+    int saveSubject(const std::shared_ptr<Subject>& subject, const QString& table);
+    int saveToken(const std::shared_ptr<Token>& token, const QString& table);
+    void saveSubjectAttributes(const std::shared_ptr<Subject>& subject, const QString& table);
     void setDeleted(const QString& id, const QString& table, quint64 time);
 
     void dropTables();
diff --git a/src/colnod/logger.cpp b/src/colnod/logger.cpp
index b06d2ef..1326479 100644
--- a/src/colnod/logger.cpp
+++ b/src/colnod/logger.cpp
@@ -1,5 +1,7 @@
 #include "logger.h"
 
+#include <utility>
+
 std::shared_ptr<DatabaseManager> Logger::dbMan = nullptr;
 Logger *Logger::logger = nullptr;
 
@@ -28,7 +30,7 @@ void Logger::logToDb(const QString &msg)
 
 void Logger::setDBMan(std::shared_ptr<DatabaseManager> dbMan)
 {
-    Logger::dbMan = dbMan;
+    Logger::dbMan = std::move(dbMan);
 }
 
 QString Logger::makeTokenMsg(const QString &tokenId, const QString &action, const QString &source)
diff --git a/src/colnod/token.cpp b/src/colnod/token.cpp
index fad1461..fcf2856 100644
--- a/src/colnod/token.cpp
+++ b/src/colnod/token.cpp
@@ -23,8 +23,7 @@ Token::Token(const QString &name)
 }
 
 Token::~Token()
-{
-}
+= default;
 
 
 void Token::fromJSON(const QJsonObject &json) {
@@ -57,7 +56,7 @@ QJsonObject Token::toJSON() const {
     return json;
 }
 
-void Token::fromSQLRecord(QSqlQuery query)
+void Token::fromSQLRecord(const QSqlQuery& query)
 {
     setId(query.value(0).toUuid());
     authErrors = query.value(1).toInt();
diff --git a/src/colnod/token.h b/src/colnod/token.h
index 953561f..abc7ff5 100644
--- a/src/colnod/token.h
+++ b/src/colnod/token.h
@@ -23,7 +23,7 @@ public:
         return lToken.getLastModified() > rToken.getLastUpdate();
     }
     friend bool operator==(const Token &lToken, const Token &rToken){
-        if (    lToken.getId() == rToken.getId() &&
+        return lToken.getId() == rToken.getId() &&
                 lToken.getName() == rToken.getName() &&
                 lToken.getDescription() == rToken.getDescription() &&
                 lToken.getLastUpdate() == rToken.getLastUpdate() &&
@@ -33,9 +33,7 @@ public:
                 lToken.timeToLive == rToken.timeToLive &&
                 lToken.authErrors == rToken.authErrors &&
                 lToken.flags == rToken.flags &&
-                lToken.subjectId == rToken.subjectId)
-            return true;
-        return false;
+                lToken.subjectId == rToken.subjectId;
     }
 
 
@@ -57,7 +55,7 @@ public:
 
     QString subjectIdToStringWithoutBraces();
 
-    void fromSQLRecord(QSqlQuery query);
+    void fromSQLRecord(const QSqlQuery& query);
     void fromJSON(const QJsonObject &json) override;
     QJsonObject toJSON() const override;