SELECT array_agg(column_name::character varying) INTO _columns
	FROM information_schema.columns 
	WHERE table_name=TG_TABLE_NAME AND table_schema=TG_TABLE_SCHEMA;

	FOR i IN array_lower(_columns,1) .. array_upper(_columns,1) LOOP
		_query='SELECT NEW.'||_columns[i]||' IS DISTINCT FROM OLD.'||_columns[i]||';';
		EXECUTE _query INTO _flag;
	END LOOP;

        IF (TG_OP = 'DELETE') THEN
		EXECUTE 'SELECT add_log('||_id_log_subtype::character varying||',3,NULL);';
		RETURN NEW;
        ELSIF (TG_OP = 'UPDATE') THEN
		SELECT array_agg(column_name::character varying) INTO _columns
		FROM information_schema.columns 
		WHERE table_name=TG_TABLE_NAME AND table_schema=TG_TABLE_SCHEMA;
		FOR i IN array_lower(_columns,1) .. array_upper(_columns,1) LOOP
			EXECUTE 'SELECT $1.'||_columns[i]||' IS DISTINCT FROM $2.'||_columns[i]||';' USING NEW,OLD INTO _flag;
			IF _flag IS TRUE THEN
				_log_dat=array_append(_log_dat,('ARRAY['''||_columns[i]||''',$1.'||_columns[i]||'::character varying]')::character varying);
			END IF;
		END LOOP;
		IF _log_dat IS NOT NULL THEN
			_query=(SELECT 'ARRAY['||array_to_string(_log_dat,',')||']')::character varying;
			EXECUTE 'SELECT add_log('||_id_log_subtype::character varying||',2,'||_query||');' USING NEW;
		END IF;
		RETURN NEW;
        ELSIF (TG_OP = 'INSERT') THEN
		SELECT 'ARRAY['||array_to_string(array_agg('ARRAY['''||column_name::character varying||''',$1.'||column_name::character varying||'::character varying]'),',')||']' INTO _query
		FROM information_schema.columns 
		WHERE table_name=TG_TABLE_NAME AND table_schema=TG_TABLE_SCHEMA;
		EXECUTE 'SELECT add_log('||_id_log_subtype::character varying||',1,'||_query||');' USING NEW;
		RETURN NEW;
        END IF;