Resolve "Improve GENERATED support"

pglablib/catalog/PgAttribute.h

@@ -11,6 +11,16 @@ class PgDatabaseCatalog;
 
 class PgAttribute {
 public:
+    enum class Identity {
+        None,
+        Always,
+        ByDefault
+    };
+    enum class Generated {
+        None,
+        Stored
+    };
+
 	using Key = std::tuple<Oid, int16_t>;
 
 	Oid relid = InvalidOid;
@@ -23,12 +33,16 @@ public:
 	bool notnull = false;
 	bool hasdef = false;
 	char identity = '\0';
+    char generated = '\0';
 	bool isdropped = false;
 	bool islocal = true;
 	Oid collation = InvalidOid;
 	QString acl;
 	QString options;
 
+    Identity getIdentity() const;
+    Generated getGenerated() const;
+
 	QString defaultValue; ///< Comes from pg_attrdef table
 	QString sername, serschema; // serial sequence name and schema
     QString description; ///< from pg_description