diff --git a/src/LicenseModel/LicenseModel.cpp b/src/LicenseModel/LicenseModel.cpp
index a36e69a..4cd7a29 100644
--- a/src/LicenseModel/LicenseModel.cpp
+++ b/src/LicenseModel/LicenseModel.cpp
@@ -1,16 +1,44 @@
 #include "LicenseModel.h"
 
+// Qt
+#include <QtSql/QSqlDatabase>
+#include <QtSql/QSqlQuery>
+#include <QtSql/QSqlError>
+#include <QDebug>
+
+// Self
+#include "../def.h"
+
 const static int COLUMN_COUNT = 9;
 
 LicenseModel::LicenseModel(QObject* parent)
     : QAbstractTableModel(parent)
 {
+    QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
+    db.setDatabaseName(DB_PATH);
 
+    if (!db.open())
+    {
+        m_status = Status::DbExistError;
+        m_errors.append("Database connection failed: " + db.lastError().text());
+    }
+    else
+    {
+        if (!checkTables())
+        {
+            m_status = Status::DbStructError;
+            m_errors.append("Database tables are not valid");
+        }
+        else
+        {
+            m_status = Status::Ok;
+        }
+    }
 }
 
 LicenseModel::~LicenseModel()
 {
-
+    m_db.close();
 }
 
 int LicenseModel::rowCount(const QModelIndex &parent) const
@@ -77,5 +105,17 @@ LicenseModel::Status LicenseModel::getStatus()
 
 QString LicenseModel::getStatusText()
 {
-    return m_errors.join('n');
+    return m_errors.join('\n');
+}
+
+bool LicenseModel::checkTables()
+{
+    bool clienttableExist = false;
+    for (const auto &table : m_db.tables())
+    {
+        if (table == "clients")
+            return true;
+    }
+    if (!clienttableExist)
+        return false;
 }
diff --git a/src/LicenseModel/LicenseModel.h b/src/LicenseModel/LicenseModel.h
index 3bb7fd4..3d5a3de 100644
--- a/src/LicenseModel/LicenseModel.h
+++ b/src/LicenseModel/LicenseModel.h
@@ -2,6 +2,7 @@
 #define LICENSEMANAGER_LICENSEMODEL_H
 
 #include <QAbstractTableModel>
+#include <QtSql/QSqlDatabase>
 
 class LicenseModel : public QAbstractTableModel
 {
@@ -41,9 +42,14 @@ public:
     Status getStatus();
     QString getStatusText();
 
+private:
+    bool checkTables();
+
 private:
     QList<LicenseItem> m_data;
+    Status m_status = Status::None;
     QStringList m_errors;
+    QSqlDatabase m_db;
 };
 
 
diff --git a/src/MainWidget/MainWidget.cpp b/src/MainWidget/MainWidget.cpp
index e4fafeb..da09aae 100644
--- a/src/MainWidget/MainWidget.cpp
+++ b/src/MainWidget/MainWidget.cpp
@@ -4,18 +4,14 @@
 #include <QHeaderView>
 #include <QLabel>
 #include <QMenu>
+#include <QMessageBox>
 #include <QPushButton>
 #include <QTableView>
 #include <QToolBar>
 #include <QVBoxLayout>
 #include <QContextMenuEvent>
 
-// Qt
-#include <QAction>
-
 // Self
-#include <QMessageBox>
-
 #include "LicenseModel/LicenseModel.h"
 
 MainWidget::MainWidget(QWidget *parent)
diff --git a/src/def.h b/src/def.h
index e542b6b..366de7a 100644
--- a/src/def.h
+++ b/src/def.h
@@ -3,6 +3,6 @@
 
 #include <QString>
 
-const static QStringView DB_PATH = "./db.sqlite";
+const static QString DB_PATH = "./db.sqlite";
 
 #endif //LICENSEMANAGER_DEF_H
\ No newline at end of file