diff --git a/src/database.cpp b/src/database.cpp
index ca189a3..5abe025 100644
--- a/src/database.cpp
+++ b/src/database.cpp
@@ -305,16 +305,12 @@ void DatabasePrivate::createChangeLogs()
 Database::Database(QObject *parent)
     : QObject(parent), d_ptr(new DatabasePrivate(this))
 {
-    Q_D(Database);
-    // d->changeLogs->sett
     DatabasePrivate::lastId++;
 }
 
 Database::Database(const Database &other, QObject *parent)
     : QObject(parent), d_ptr(new DatabasePrivate(this))
 {
-    Q_D(Database);
-
     DatabasePrivate::lastId++;
 
     setDriver(other.driver());
@@ -392,7 +388,6 @@ DatabaseModel Database::model() const
 
 QString Database::tableName(QString className)
 {
-    Q_D(Database);
     TableModel *m = model().tableByClassName(className);
     if (m)
         return m->name();
@@ -514,20 +509,23 @@ QSqlQuery Database::exec(QString sql)
 
 void Database::add(TableSetBase *t)
 {
-    tableSets.insert(t);
+    Q_D(Database);
+    d->tableSets.insert(t);
 }
 
-int Database::saveChanges()
+int Database::saveChanges(bool cleanUp)
 {
+    Q_D(Database);
     int rowsAffected = 0;
-    foreach (TableSetBase *ts, tableSets)
-        rowsAffected += ts->save(this);
+    foreach (TableSetBase *ts, d->tableSets)
+        rowsAffected += ts->save(this, cleanUp);
     return rowsAffected;
 }
 
 void Database::cleanUp()
 {
-    foreach (TableSetBase *ts, tableSets)
+    Q_D(Database);
+    foreach (TableSetBase *ts, d->tableSets)
         ts->clearChilds();
 }
 
diff --git a/src/database.h b/src/database.h
index 705daed..4166e69 100644
--- a/src/database.h
+++ b/src/database.h
@@ -53,9 +53,7 @@ public:
 
     QSqlQuery exec(QString sql);
 
-    //TODO: make me private and rename me
-    void add(TableSetBase *);
-    int saveChanges();
+    int saveChanges(bool cleanUp = false);
     void cleanUp();
 
     QString databaseName() const;
@@ -86,8 +84,9 @@ public slots:
     void setDriver(QString driver);
 
 private:
-    //TODO: move me to database_p.h
-    QSet<TableSetBase *> tableSets;
+    void add(TableSetBase *);
+
+    friend class TableSetBase;
 };
 
 NUT_END_NAMESPACE
diff --git a/src/database_p.h b/src/database_p.h
index ac01411..33c4b05 100644
--- a/src/database_p.h
+++ b/src/database_p.h
@@ -37,7 +37,6 @@ class DatabasePrivate
 public:
     DatabasePrivate(Database *parent);
 
-
     bool open(bool updateDatabase);
 
     bool updateDatabase();
@@ -56,7 +55,6 @@ public:
     QString connectionName;
     QString driver;
 
-
     SqlGeneratorBase *sqlGenertor;
     DatabaseModel currentModel;
 
@@ -66,6 +64,8 @@ public:
     QHash<QString, QString> tables;
     static QMap<QString, DatabaseModel> allTableMaps;
     static int lastId;
+
+    QSet<TableSetBase *> tableSets;
 };
 
 NUT_END_NAMESPACE
diff --git a/src/mysqlgenerator.cpp b/src/mysqlgenerator.cpp
index 44f6fb9..f2d4c1a 100644
--- a/src/mysqlgenerator.cpp
+++ b/src/mysqlgenerator.cpp
@@ -120,6 +120,7 @@ QVariant MySqlGenerator::readValue(const QVariant::Type &type, const QVariant &d
     if (type == QVariant::PointF) {
         qDebug() << "QVariant::PointF" << dbValue;
     }
+    return SqlGeneratorBase::readValue(type, dbValue);
 }
 
 QString MySqlGenerator::phrase(const PhraseData *d) const
diff --git a/src/postgresqlgenerator.cpp b/src/postgresqlgenerator.cpp
index b0eb3d0..0ff4b46 100644
--- a/src/postgresqlgenerator.cpp
+++ b/src/postgresqlgenerator.cpp
@@ -95,7 +95,7 @@ QString PostgreSqlGenerator::fieldType(FieldModel *field)
         dbType = "";
     }
 
-    if(field->type == QMetaType::type("Nut::DbGeography"))
+    if(field->type == (unsigned)QMetaType::type("Nut::DbGeography"))
         dbType = "GEOGRAPHY";
 
     return dbType;
diff --git a/src/query.h b/src/query.h
index 937f90e..a14b845 100644
--- a/src/query.h
+++ b/src/query.h
@@ -64,6 +64,8 @@ public:
     Query<T> *skip(int &n);
     Query<T> *take(int &n);
     Query<T> *orderBy(WherePhrase phrase);
+    Query<T> *include(TableSetBase *t);
+    Query<T> *include(Table *t);
 
     int count();
     QVariant max(FieldPhrase<int> &f);
@@ -355,6 +357,22 @@ Q_OUTOFLINE_TEMPLATE Query<T> *Query<T>::orderBy(WherePhrase phrase)
     return this;
 }
 
+template <class T>
+Q_OUTOFLINE_TEMPLATE Query<T> *Query<T>::include(TableSetBase *t)
+{
+    Q_D(Query);
+    d->joinClassName = t->childClassName();
+    return this;
+}
+
+template <class T>
+Q_OUTOFLINE_TEMPLATE Query<T> *Query<T>::include(Table *t)
+{
+    Q_D(Query);
+    d->joinClassName = t->metaObject()->className();
+    return this;
+}
+
 template <class T>
 Q_OUTOFLINE_TEMPLATE int Query<T>::update(WherePhrase phrase)
 {
diff --git a/src/querybase_p.h b/src/querybase_p.h
index 087c714..c5f370d 100644
--- a/src/querybase_p.h
+++ b/src/querybase_p.h
@@ -27,6 +27,7 @@
 
 NUT_BEGIN_NAMESPACE
 
+//TODO: remove this class
 class QueryBase : public QObject
 {
     Q_OBJECT
diff --git a/src/sqlgeneratorbase.cpp b/src/sqlgeneratorbase.cpp
index 43c1f02..4876d0f 100644
--- a/src/sqlgeneratorbase.cpp
+++ b/src/sqlgeneratorbase.cpp
@@ -187,7 +187,7 @@ QString SqlGeneratorBase::insertRecord(Table *t, QString tableName)
               .arg(changedPropertiesText)
               .arg(values.join(", "));
 
-    replaceTableNames(sql);
+    removeTableNames(sql);
 
     return sql;
 }
@@ -208,7 +208,7 @@ QString SqlGeneratorBase::updateRecord(Table *t, QString tableName)
               .arg(key)
               .arg(t->primaryValue().toString());
 
-    replaceTableNames(sql);
+    removeTableNames(sql);
 
     return sql;
 }
@@ -309,6 +309,9 @@ QString SqlGeneratorBase::selectCommand(SqlGeneratorBase::AgregateType t,
                                         QString tableName,
                                         QString joinClassName, int skip, int take)
 {
+    Q_UNUSED(take);
+    Q_UNUSED(skip);
+
     QString select = agregateText(t, agregateArg);
     QString where = createWhere(wheres);
     QString order = "";
@@ -354,7 +357,13 @@ QString SqlGeneratorBase::createWhere(QList<WherePhrase> &wheres)
 void SqlGeneratorBase::replaceTableNames(QString &command)
 {
     foreach (TableModel *m, TableModel::allModels())
-        command = command.replace("[" + m->className() + "].", m->name() + ".");
+        command = command.replace("[" + m->className() + "].", "`" + m->name() + "`.");
+}
+
+void SqlGeneratorBase::removeTableNames(QString &command)
+{
+    foreach (TableModel *m, TableModel::allModels())
+        command = command.replace("[" + m->className() + "].", "");
 }
 
 QString SqlGeneratorBase::deleteCommand(QList<WherePhrase> &wheres,
@@ -391,11 +400,19 @@ QString SqlGeneratorBase::updateCommand(WherePhrase &phrase,
         sql = sql.replace(_database->model().at(i)->className() + ".",
                           _database->model().at(i)->name() + ".");
 
-    replaceTableNames(sql);
+    removeTableNames(sql);
 
     return sql;
 }
 
+QString SqlGeneratorBase::joinTables(QStringList tables)
+{
+    Q_UNUSED(tables);
+    //TODO: implement me
+//    _database->model().relationByClassNames()
+    return "";
+}
+
 QString SqlGeneratorBase::escapeValue(const QVariant &v) const
 {
     switch (v.type()) {
@@ -441,13 +458,16 @@ QString SqlGeneratorBase::escapeValue(const QVariant &v) const
     case QVariant::Invalid:
         qFatal("Invalud field value");
         return "<FAIL>";
+
+    default:
+        return "";
     }
-    return "";
 }
 
 QVariant SqlGeneratorBase::readValue(const QVariant::Type &type,
                                      const QVariant &dbValue)
 {
+    Q_UNUSED(type);
     return dbValue;
 }
 
@@ -601,9 +621,10 @@ SqlGeneratorBase::operatorString(const PhraseData::Condition &cond) const
 
     case PhraseData::Append:
         return ",";
-    }
 
-    return QString("<FAIL>");
+    default:
+        return QString("<FAIL>");
+    }
 }
 
 NUT_END_NAMESPACE
diff --git a/src/sqlgeneratorbase_p.h b/src/sqlgeneratorbase_p.h
index 3aba191..9714948 100644
--- a/src/sqlgeneratorbase_p.h
+++ b/src/sqlgeneratorbase_p.h
@@ -88,6 +88,8 @@ public:
 
     virtual QString updateCommand(WherePhrase &phrase, QList<WherePhrase> &wheres, QString tableName);
 
+    virtual QString joinTables(QStringList tables);
+
     virtual QString escapeValue(const QVariant &v) const;
     virtual QVariant readValue(const QVariant::Type &type, const QVariant &dbValue);
     virtual QString phrase(const PhraseData *d) const;
@@ -100,6 +102,7 @@ private:
     QString createWhere(QList<WherePhrase> &wheres);
     QString phraseOrder(const PhraseData *d) const;
     void replaceTableNames(QString &command);
+    void removeTableNames(QString &command);
 };
 
 NUT_END_NAMESPACE
diff --git a/src/table.h b/src/table.h
index 8e369f3..da9f8cb 100644
--- a/src/table.h
+++ b/src/table.h
@@ -48,7 +48,6 @@ public:
         Deleted
     };
 
-    void add(TableSetBase *);
     int save(Database *db);
 
     QString primaryKey() const;
@@ -77,9 +76,12 @@ private:
 
     QSet<TableSetBase*> tableSets;
     void clear();
+    void add(TableSetBase *);
 
     template<class T>
     friend class Query;
+
+    friend class TableSetBase;
 };
 
 NUT_END_NAMESPACE
diff --git a/src/tablemodel.h b/src/tablemodel.h
index 3e2b9c6..700032e 100644
--- a/src/tablemodel.h
+++ b/src/tablemodel.h
@@ -38,6 +38,7 @@ struct FieldModel{
     }
 
     QString name;
+    //TODO: QMetaType::Type??
     QVariant::Type type;
     QString typeName;
     int length;
diff --git a/src/tablesetbase.cpp b/src/tablesetbase.cpp
index e9bc7f5..1891885 100644
--- a/src/tablesetbase.cpp
+++ b/src/tablesetbase.cpp
@@ -35,7 +35,7 @@ TableSetBase::TableSetBase(Table *parent) : QObject(parent), _database(0), _tabl
     parent->add(this);
 }
 
-int TableSetBase::save(Database *db)
+int TableSetBase::save(Database *db, bool cleanUp)
 {
     int rowsAffected = 0;
     foreach (Table *t, _tablesList) {
@@ -46,16 +46,23 @@ int TableSetBase::save(Database *db)
                 || t->status() == Table::Modified
                 || t->status() == Table::Deleted){
             rowsAffected += t->save(db);
+
+            if(cleanUp)
+                t->deleteLater();
         }
     }
 
+    if (cleanUp)
+        _tablesList.clear();
+
     return rowsAffected;
 }
 
 void TableSetBase::clearChilds()
 {
     foreach (Table *t, _tablesList)
-        delete t;
+        t->deleteLater();
+    _tablesList.clear();
 }
 
 void TableSetBase::add(Table *t)
diff --git a/src/tablesetbase_p.h b/src/tablesetbase_p.h
index 50dd5a6..68f7df0 100644
--- a/src/tablesetbase_p.h
+++ b/src/tablesetbase_p.h
@@ -38,7 +38,7 @@ public:
     TableSetBase(Database *parent);
     TableSetBase(Table *parent);
 
-    virtual int save(Database *db);
+    virtual int save(Database *db, bool cleanUp = false);
     void clearChilds();
     void add(Table* t);
     QString childClassName() const;
diff --git a/test/basic/maintest.cpp b/test/basic/maintest.cpp
index 7bb0b6d..5365825 100644
--- a/test/basic/maintest.cpp
+++ b/test/basic/maintest.cpp
@@ -26,12 +26,15 @@ void MainTest::initTestCase()
 
     db.setDriver(DRIVER);
     db.setHostName(HOST);
-    db.setDatabaseName(DATABASE);
+    db.setDatabaseName("nut_tst_basic");
     db.setUserName(USERNAME);
     db.setPassword(PASSWORD);
 
     bool ok = db.open();
 
+    db.comments()->query()->remove();
+    db.posts()->query()->remove();
+
     QTEST_ASSERT(ok);
 }
 
@@ -116,10 +119,17 @@ void MainTest::selectPostsWithoutTitle()
     auto q = db.posts()->query();
     q->setWhere(Post::titleField().isNull());
     auto count = q->count();
-    qDebug() << "selectPostsWithoutTitle, count=" << count;
+    qDebug() << q->sqlCommand();
     QTEST_ASSERT(count == 0);
 }
 
+void MainTest::selectPostIds()
+{
+    auto ids = db.posts()->query()->select(Post::idField());
+
+    QTEST_ASSERT(ids.count() == 2);
+}
+
 void MainTest::testDate()
 {
     QDateTime d = QDateTime::currentDateTime();
@@ -177,18 +187,11 @@ void MainTest::modifyPost()
 
 void MainTest::emptyDatabase()
 {
-    auto count = db.posts()->query()
-            ->setWhere(Post::idField() == postId)
-            ->remove();
+    auto commentsCount = db.comments()->query()->remove();
+    auto postsCount = db.posts()->query()->remove();
 
-    QTEST_ASSERT(count == 1);
-
-    count = db.posts()->query()
-            ->setWhere(Post::idField() == postId)
-            ->count();
-
-    QTEST_ASSERT(count == 0);
+    QTEST_ASSERT(postsCount == 3);
+    QTEST_ASSERT(commentsCount == 6);
 }
 
-
 QTEST_MAIN(MainTest)
diff --git a/test/basic/maintest.h b/test/basic/maintest.h
index 7689640..2d55666 100644
--- a/test/basic/maintest.h
+++ b/test/basic/maintest.h
@@ -25,6 +25,7 @@ private slots:
     void createPost2();
     void selectPosts();
     void selectPostsWithoutTitle();
+    void selectPostIds();
     void testDate();
     void selectWithInvalidRelation();
     void select10NewstPosts();
diff --git a/test/common/consts.h b/test/common/consts.h
index 96cb683..9475fa9 100644
--- a/test/common/consts.h
+++ b/test/common/consts.h
@@ -1,17 +1,17 @@
 #ifndef CONSTS_H
 #define CONSTS_H
 
-#define DRIVER "QPSQL"
-#define HOST "127.0.0.1"
-#define DATABASE "nutdb2"
-#define USERNAME "postgres"
-#define PASSWORD "856856"
-
-//#define DRIVER "QMYSQL"
+//#define DRIVER "QPSQL"
 //#define HOST "127.0.0.1"
-//#define DATABASE "nutdb"
-//#define USERNAME "root"
-//#define PASSWORD "onlyonlyi"
+//#define DATABASE "nutdb2"
+//#define USERNAME "postgres"
+//#define PASSWORD "856856"
+
+#define DRIVER "QMYSQL"
+#define HOST "127.0.0.1"
+#define DATABASE "nutdb"
+#define USERNAME "root"
+#define PASSWORD "onlyonlyi"
 
 //#define DRIVER "QODBC"
 //#define HOST "127.0.0.1"