diff --git a/application/application.pro b/application/application.pro
index 5ec912f..a1e2144 100644
--- a/application/application.pro
+++ b/application/application.pro
@@ -4,7 +4,7 @@
 #
 #-------------------------------------------------
 
-QT       += core gui
+QT       += core gui sql
 
 greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
 
diff --git a/core/autotablemodel.h b/core/autotablemodel.h
index 9293e59..206079d 100644
--- a/core/autotablemodel.h
+++ b/core/autotablemodel.h
@@ -20,33 +20,6 @@ public:
 
     virtual ~AutoTableModel() {}
 
-private:
-    class Comparator
-    {
-    public:
-        Comparator(const QString &property, Qt::SortOrder order)
-        {
-            m_property = property;
-            m_order = order;
-        }
-
-        bool operator()(QSharedPointer<T> entA, QSharedPointer<T> entB) {
-            QObject *rawEntityA = (QObject*)entA.data();
-            QObject *rawEntityB = (QObject*)entB.data();
-
-            if (m_order == Qt::AscendingOrder) {
-                return rawEntityA->property(m_property.toStdString().c_str()) < rawEntityB->property(m_property.toStdString().c_str());
-            } else {
-                return rawEntityB->property(m_property.toStdString().c_str()) < rawEntityA->property(m_property.toStdString().c_str());
-            }
-        }
-
-    private:
-        QString m_property;
-        Qt::SortOrder m_order;
-    };
-
-
     // QAbstractItemModel interface
 public:
     int rowCount(const QModelIndex &parent = QModelIndex()) const
@@ -117,10 +90,18 @@ public:
         }
 
         beginResetModel();
+
         QObject *rawEntity = (QObject*)m_list.at(0).data();
-        Comparator c(rawEntity->metaObject()->property(column + 1).name(), order);
+        const char *prop = rawEntity->metaObject()->property(column + 1).name();
+
+        std::sort(m_list.begin(), m_list.end(), [prop, order](QSharedPointer<T> entA, QSharedPointer<T> entB) -> bool {
+            if (order == Qt::AscendingOrder) {
+                return ((QObject*)entA.data())->property(prop) < ((QObject*)entB.data())->property(prop);
+            } else {
+                return ((QObject*)entB.data())->property(prop) < ((QObject*)entA.data())->property(prop);
+            }
+        });
 
-        std::sort(m_list.begin(), m_list.end(), c);
         endResetModel();
     }
 
diff --git a/core/context.cpp b/core/context.cpp
index 5e20837..4346eaf 100644
--- a/core/context.cpp
+++ b/core/context.cpp
@@ -1,10 +1,16 @@
 #include <QDir>
 #include <QApplication>
 #include <QPluginLoader>
+#include <QSqlDatabase>
+#include <QSqlQuery>
+#include <QSqlResult>
+#include <QSqlError>
+#include <QDebug>
 
 #include <odb/sqlite/database.hxx>
 
 #include "core.h"
+#include "coreplugin.h"
 
 Context &Context::instance()
 {
@@ -17,8 +23,22 @@ QList<IPlugin *> Context::plugins()
     return m_plugins;
 }
 
+IPlugin *Context::plugin(const QString &pluginId)
+{
+    QList<IPlugin*>::iterator it = std::find_if(m_plugins.begin(), m_plugins.end(), [&pluginId](IPlugin *p) { return p->pluginId() == pluginId; });
+    if (it != m_plugins.end())
+    {
+        return *it;
+    }
+
+    return NULL;
+}
+
 void Context::loadPlugins()
 {
+    IPlugin *corePlugin = new CorePlugin();
+    m_plugins.append(corePlugin);
+
     QDir pluginsDir(qApp->applicationDirPath() + "/../../plugins");
 
     foreach (QString fileName, pluginsDir.entryList(QStringList() << "*.so" << "*.dll")) {
@@ -41,6 +61,7 @@ void Context::openDb(const QString &path)
         delete m_db;
     }
 
+    checkDb(path);
     m_db = new odb::sqlite::database(path.toStdString());
 }
 
@@ -48,3 +69,68 @@ Context::Context()
 {
     m_db = NULL;
 }
+
+void Context::checkDb(const QString &path)
+{
+    QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
+    db.setDatabaseName(path);
+    db.open();
+    QSqlQuery q(db);
+    QString verSql = "SELECT pluginId, schemaVersion FROM system";
+    QString createSysSql = "CREATE TABLE \"system\" (\"id\" INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT, \"pluginId\" TEXT NULL, \"schemaVersion\" TEXT NULL)";
+
+    if (q.exec(verSql))
+    {
+        QMap<QString, int> schemas;
+        while (q.next())
+        {
+            schemas[q.value("pluginId").toString()] = q.value("schemaVersion").toInt();
+        }
+        checkSchema(db, schemas);
+    }
+    else
+    {
+        q.exec(createSysSql);
+        checkSchema(db, QMap<QString, int>());
+    }
+
+    db.close();
+}
+
+void Context::checkSchema(const QSqlDatabase &db, const QMap<QString, int> &schemaMap)
+{
+    foreach (IPlugin *plugin, m_plugins) {
+        if (!schemaMap.contains(plugin->pluginId()) || schemaMap[plugin->pluginId()] < plugin->schemaVersion())
+        {
+            int ver = schemaMap[plugin->pluginId()];
+
+            for (int i = 0; i < plugin->schemas().count(); i++)
+            {
+                if (!schemaMap.contains(plugin->pluginId()) || i >= ver)
+                {
+                    QString sql = plugin->schemas()[i];
+                    QSqlQuery q(db);
+
+                    QStringList sqlList = sql.split(";");
+
+                    foreach (QString s, sqlList) {
+                        if (!q.exec(s))
+                        {
+                            qDebug() << q.lastError().text();
+                        }
+                    }
+
+                    if (ver == 0)
+                    {
+                        sql = "INSERT INTO system(pluginId, schemaVersion) VALUES('" + plugin->pluginId() + "', 1)";
+                    }
+                    else
+                    {
+                        sql = "UPDATE system SET schemaVersion = " + QString::number(i + 1) + " WHERE pluginId = '" + plugin->pluginId() + "'";
+                    }
+                    q.exec(sql);
+                }
+            }
+        }
+    }
+}
diff --git a/core/context.h b/core/context.h
index b398680..6ce07b3 100644
--- a/core/context.h
+++ b/core/context.h
@@ -2,6 +2,10 @@
 #define CONTEXT_H
 
 #include <QList>
+#include <QMap>
+#include <QString>
+#include <QSqlDatabase>
+
 #include "core_global.h"
 #include "transaction.h"
 
@@ -14,6 +18,7 @@ class CORESHARED_EXPORT Context
 public:
     static Context &instance();
     QList<IPlugin*> plugins();
+    IPlugin *plugin(const QString &pluginId);
     void loadPlugins();
     void openDb(const QString &path);
     odb::database *db() { return m_db; }
@@ -22,6 +27,9 @@ private:
     Context();
     QList<IPlugin*> m_plugins;
     odb::database *m_db;
+
+    void checkDb(const QString &path);
+    void checkSchema(const QSqlDatabase &db, const QMap<QString, int> &schemaMap);
 };
 
 #endif // CONTEXT_H
diff --git a/core/core.pro b/core/core.pro
index 688fad0..b4b03d4 100644
--- a/core/core.pro
+++ b/core/core.pro
@@ -4,7 +4,7 @@
 #
 #-------------------------------------------------
 
-QT       += widgets
+QT       += widgets sql
 
 TARGET = core
 TEMPLATE = lib
@@ -18,7 +18,8 @@ SOURCES += \
     transaction.cpp \
     emptystringvalidator.cpp \
     data/role.cpp \
-    data/permission.cpp
+    data/permission.cpp \
+    coreplugin.cpp
 
 HEADERS += core.h\
         core_global.h \
@@ -34,7 +35,8 @@ HEADERS += core.h\
     emptystringvalidator.h \
     data/role.h \
     data/permission.h \
-    data/core-data.h
+    data/core-data.h \
+    coreplugin.h
 
 unix {
     target.path = /usr/lib
@@ -45,3 +47,9 @@ ODB_FILES = core/data/core-data.h
 
 H_DIR = $$PWD/data/*.h
 include(../odb.pri)
+
+RESOURCES += \
+    rc.qrc
+
+DISTFILES += \
+    metaData.json
diff --git a/core/coreplugin.cpp b/core/coreplugin.cpp
new file mode 100644
index 0000000..ad7026b
--- /dev/null
+++ b/core/coreplugin.cpp
@@ -0,0 +1,25 @@
+#include "coreplugin.h"
+#include <QJsonDocument>
+#include <QFile>
+
+CorePlugin::CorePlugin()
+{
+    Q_INIT_RESOURCE(rc);
+
+    QFile f(":/metaData.json");
+    f.open(QIODevice::ReadOnly | QIODevice::Text);
+    QJsonDocument d = QJsonDocument::fromJson(f.readAll());
+    init(d.object());
+    f.close();
+}
+
+CorePlugin::~CorePlugin()
+{
+}
+
+void CorePlugin::initServiceUi()
+{
+    m_service = NULL;
+    m_ui = NULL;
+}
+
diff --git a/core/coreplugin.h b/core/coreplugin.h
new file mode 100644
index 0000000..c1b1f29
--- /dev/null
+++ b/core/coreplugin.h
@@ -0,0 +1,17 @@
+#ifndef COREPLUGIN_H
+#define COREPLUGIN_H
+
+#include "imetadataplugin.h"
+
+class CorePlugin : public IMetaDataPlugin
+{
+public:
+    CorePlugin();
+    ~CorePlugin();
+
+    // IMetaDataPlugin interface
+protected:
+    virtual void initServiceUi();
+};
+
+#endif // COREPLUGIN_H
diff --git a/core/imetadataplugin.cpp b/core/imetadataplugin.cpp
index ef96efc..f14760d 100644
--- a/core/imetadataplugin.cpp
+++ b/core/imetadataplugin.cpp
@@ -1,6 +1,7 @@
 #include "imetadataplugin.h"
 
 #include <QJsonValue>
+#include <QJsonArray>
 #include <QLocale>
 #include <QDebug>
 
@@ -27,6 +28,16 @@ QString IMetaDataPlugin::pluginDescription()
     return m_description;
 }
 
+int IMetaDataPlugin::schemaVersion()
+{
+    return m_schemaVersion;
+}
+
+QStringList IMetaDataPlugin::schemas()
+{
+    return m_schemas;
+}
+
 void IMetaDataPlugin::init(const QJsonObject &metaData)
 {
     parseMetaData(metaData);
@@ -44,6 +55,11 @@ void IMetaDataPlugin::parseMetaData(const QJsonObject &metaData)
     m_name = parseLocaleText(data.toObject()["name"].toObject());
     m_description = parseLocaleText(data.toObject()["description"].toObject());
     m_id = data.toObject()["id"].toString();
+    m_schemaVersion = data.toObject()["schemaVersion"].toInt();
+
+    foreach (QJsonValue schVal, data.toObject()["sql"].toArray()) {
+        m_schemas.append(schVal.toString());
+    }
 }
 
 QString IMetaDataPlugin::parseLocaleText(const QJsonObject &object)
diff --git a/core/imetadataplugin.h b/core/imetadataplugin.h
index 463f5aa..5ee3c0a 100644
--- a/core/imetadataplugin.h
+++ b/core/imetadataplugin.h
@@ -17,6 +17,8 @@ public:
     virtual QString pluginName();
     virtual QString pluginId();
     virtual QString pluginDescription();
+    virtual int schemaVersion();
+    virtual QStringList schemas();
     virtual void init(const QJsonObject &metaData);
 
 protected:
@@ -27,6 +29,8 @@ private:
     QString m_name;
     QString m_id;
     QString m_description;
+    int m_schemaVersion;
+    QStringList m_schemas;
 
     QString parseLocaleText(const QJsonObject &object);
 };
diff --git a/core/iplugin.h b/core/iplugin.h
index 0682550..96ad791 100644
--- a/core/iplugin.h
+++ b/core/iplugin.h
@@ -5,6 +5,7 @@
 #include <QWidget>
 #include <QtPlugin>
 #include <QJsonObject>
+#include <QStringList>
 
 #include "service.h"
 
@@ -20,6 +21,8 @@ public:
     virtual QString pluginName() = 0;
     virtual QString pluginId() = 0;
     virtual QString pluginDescription() = 0;
+    virtual int schemaVersion() = 0;
+    virtual QStringList schemas() = 0;
     virtual void init(const QJsonObject &metaData) = 0;
     virtual QWidget *ui() {
         return m_ui;
diff --git a/core/metaData.json b/core/metaData.json
new file mode 100644
index 0000000..7a513dc
--- /dev/null
+++ b/core/metaData.json
@@ -0,0 +1,73 @@
+{
+    "MetaData" : {
+    "id" : "CORE",
+    "name" : {
+        "default" : "Core plugin",
+        "CZ" : "Jádro"
+    },
+    "descriptoin" : {
+        "default" : "",
+        "CZ" : ""
+    },
+    "schemaVersion" : 1,
+    "sql" : [
+        "CREATE TABLE \"User\" (
+          \"id\" INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
+          \"login\" TEXT NULL,
+          \"password\" TEXT NULL,
+          \"name\" TEXT NULL,
+          \"lastModDate\" TEXT NULL,
+          \"createDate\" TEXT NULL,
+          \"active\" INTEGER NOT NULL,
+          \"isAdmin\" INTEGER NOT NULL);
+
+        CREATE TABLE \"User_listRoles\" (
+          \"object_id\" INTEGER NOT NULL,
+          \"value\" INTEGER NOT NULL,
+          CONSTRAINT \"object_id_fk\"
+            FOREIGN KEY (\"object_id\")
+            REFERENCES \"User\" (\"id\")
+            ON DELETE CASCADE,
+          CONSTRAINT \"value_fk\"
+            FOREIGN KEY (\"value\")
+            REFERENCES \"Role\" (\"id\")
+            DEFERRABLE INITIALLY DEFERRED);
+
+        CREATE INDEX \"User_listRoles_object_id_i\"
+          ON \"User_listRoles\" (\"object_id\");
+
+        CREATE TABLE \"Role\" (
+          \"id\" INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
+          \"name\" TEXT NULL,
+          \"lastModDate\" TEXT NULL,
+          \"createDate\" TEXT NULL,
+          \"active\" INTEGER NOT NULL);
+
+        CREATE TABLE \"Role_listPermissions\" (
+          \"object_id\" INTEGER NOT NULL,
+          \"value\" INTEGER NOT NULL,
+          CONSTRAINT \"object_id_fk\"
+            FOREIGN KEY (\"object_id\")
+            REFERENCES \"Role\" (\"id\")
+            ON DELETE CASCADE,
+          CONSTRAINT \"value_fk\"
+            FOREIGN KEY (\"value\")
+            REFERENCES \"Permission\" (\"id\")
+            DEFERRABLE INITIALLY DEFERRED);
+
+        CREATE INDEX \"Role_listPermissions_object_id_i\"
+          ON \"Role_listPermissions\" (\"object_id\");
+
+        CREATE TABLE \"Permission\" (
+          \"id\" INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
+          \"pluginId\" TEXT NULL,
+          \"permissionName\" TEXT NULL,
+          \"lastModDate\" TEXT NULL,
+          \"createDate\" TEXT NULL,
+          \"active\" INTEGER NOT NULL);"
+
+
+    ],
+    "dependencies" : []
+    }
+}
diff --git a/core/rc.qrc b/core/rc.qrc
new file mode 100644
index 0000000..681c9be
--- /dev/null
+++ b/core/rc.qrc
@@ -0,0 +1,5 @@
+<RCC>
+    <qresource prefix="/">
+        <file>metaData.json</file>
+    </qresource>
+</RCC>
diff --git a/core/service.h b/core/service.h
index 821756d..ab353e9 100644
--- a/core/service.h
+++ b/core/service.h
@@ -3,6 +3,7 @@
 
 #include <QList>
 #include <QSharedPointer>
+#include <QString>
 
 #include <odb/core.hxx>
 #include <odb/transaction.hxx>
@@ -39,6 +40,9 @@ public:
 
     void save(QSharedPointer<T> entity) {
         odb::database *db = Context::instance().db();
+
+        Q_ASSERT(db);
+
         Transaction tx;
         db->persist(entity);
         tx.commit();
@@ -46,11 +50,21 @@ public:
 
     QSharedPointer<T> loadById(int id) {
         odb::database *db = Context::instance().db();
+
+        Q_ASSERT(db);
+
         Transaction tx;
         QSharedPointer<T> entity = db->template load<T>(id);
         tx.commit();
         return entity;
     }
+
+    void setPluginId(const QString &pluginId) {
+        m_pluginId = pluginId;
+    }
+
+private:
+    QString m_pluginId;
 };
 
 #endif // SERVICE_H
diff --git a/core/transaction.cpp b/core/transaction.cpp
index 8090274..412d450 100644
--- a/core/transaction.cpp
+++ b/core/transaction.cpp
@@ -11,6 +11,10 @@ Transaction::Transaction()
         m_tr = new odb::transaction(Context::instance().db()->begin());
         Transaction::m_inTransaction = true;
     }
+    else
+    {
+        m_tr = NULL;
+    }
 }
 
 Transaction::~Transaction()