lazy load the database sizes only when needed by the server inspector.

pglab/DatabasesTableModel.h

@@ -2,11 +2,11 @@
 #define DATABASESTABLEMODEL_H
 
 #include "BaseTableModel.h"
+#include "catalog/PgDatabase.h"
 #include <memory>
 
-class PgDatabaseContainer;
+class OpenDatabase;
 class PgDatabaseCatalog;
-class PgDatabase;
 
 /** Class for displaying the list of databases of a server in a QTableView
  *
@@ -24,7 +24,7 @@ public:
 
 
 
-	explicit DatabasesTableModel(QObject *parent);
+    explicit DatabasesTableModel(std::shared_ptr<OpenDatabase> opendatabase, QObject *parent);
 
 	void setDatabaseList(std::shared_ptr<const PgDatabaseCatalog> cat);
 
@@ -41,8 +41,36 @@ public:
 protected:
     virtual QVariant getDataMeaning(const QModelIndex &index) const override;
 private:
+    class DatabaseSize {
+    public:
+        Oid oid;
+        int64_t totalBytes;
+
+        DatabaseSize()
+            : oid(InvalidOid)
+            , totalBytes(-1)
+        {}
+    };
+    using DatabaseSizes = std::vector<DatabaseSize>;
+
+    class Database {
+    public:
+        PgDatabase database;
+        DatabaseSize size;
+
+        Database(const PgDatabase &db)
+            : database(db)
+        {}
+    };
+    using Databases = std::vector<Database>;
+
+    std::shared_ptr<OpenDatabase> openDatabase;
 	std::shared_ptr<const PgDatabaseCatalog> m_catalog;
-	std::shared_ptr<const PgDatabaseContainer> m_databases;
+    Databases databases;
+
+    void StartLoadDatabaseSizes(std::map<Oid, int> oidIndex);
+    DatabaseSizes QueryDatabaseSizes();
+    void PopulateSizes(std::map<Oid, int> oidIndex, DatabaseSizes sizes);
 };
 
 #endif // DATABASESTABLEMODEL_H