CHYBA:
Chyba sql dotazu:

		SELECT 
			ws.id, ws.id AS web_strom_id, 
			0, 
			ws.rodic_id, ws.poradi,
			wsm.moduly, wsm.moduly_ids,
			s.id AS stranka_id, s.titulek, s.aktivni, sl.langs
		FROM
			web_strom AS ws
		LEFT JOIN
			stranka AS s
			ON
				s.web_strom_id = ws.id
		LEFT JOIN 
			(
				SELECT web_strom_id, GROUP_CONCAT(lang, ",") AS langs
				FROM stranka
				GROUP BY web_strom_id
			) AS sl
			ON
				sl.web_strom_id = s.web_strom_id
		LEFT JOIN 
			(
				SELECT web_strom_id, GROUP_CONCAT(modul, ",") AS moduly, GROUP_CONCAT(modul_id, ",") AS moduly_ids
				FROM web_strom_modul
				GROUP BY web_strom_id
				ORDER BY poradi
			) AS wsm
			ON
				wsm.web_strom_id = ws.id
		WHERE TRUE
			AND ws.id = "1000004"
			AND s.lang = "cz"
			AND s.smazano = "0"
		ORDER BY ws.rodic_id, ws.poradi