poc Add support for reloading the catalog

Reload works and the column page reacts correctly. Others to be checked
and fixed.

pglab/ColumnTableModel.h

@@ -3,6 +3,7 @@
 
 #include "BaseTableModel.h"
 #include "catalog/PgAttribute.h"
+#include "catalog/PgDatabaseCatalog.h"
 #include "catalog/PgClass.h"
 #include "catalog/PgIndex.h"
 #include <memory>
@@ -13,6 +14,7 @@ class PgDatabaseCatalog;
 class PgAttribute;
 
 class ColumnTableModel: public BaseTableModel {
+	Q_OBJECT
 public:
 	enum e_Columns : int {
 		AttnumCol,
@@ -49,8 +51,15 @@ protected:
 	t_Columns m_columns;
 	std::vector<PgIndex> m_indexes;
 
+	QMetaObject::Connection refreshConnection;
+
 	QString getFKey(const PgAttribute &column) const;
 
+
+
+private slots:
+	/// Retrieves required data from catalog, called everytime it might have changed
+	void refresh();
 };
 
 #endif // COLUMNTABLEMODEL_H