Out of memory; check if mysqld or some other process uses all available memory; if not, you may have to use 'ulimit' to allow mysqld to use more memory or you can add more swap space
select BLID, BLNAME, BLDETAIL from FLC_BL where BLNAME in ( select BLNAME from ( select BLNAME from FLC_BL where BLTYPE = 'JS' and BLGLOBAL = 1 union select TRIGGER_BL from FLC_TRIGGER where TRIGGER_STATUS = 1 and TRIGGER_TYPE = 'JS' and TRIGGER_ITEM_TYPE = 'page' and TRIGGER_ITEM_ID = 31 union select TRIGGER_BL from FLC_TRIGGER where TRIGGER_STATUS = 1 and TRIGGER_TYPE = 'JS' and TRIGGER_ITEM_TYPE = 'component' and TRIGGER_ITEM_ID in (select COMPONENTID from FLC_PAGE_COMPONENT where PAGEID = 31) union select TRIGGER_BL from FLC_TRIGGER where TRIGGER_STATUS = 1 and TRIGGER_TYPE = 'JS' and TRIGGER_ITEM_TYPE = 'item' and TRIGGER_ITEM_ID in (select ITEMID from FLC_PAGE_COMPONENT_ITEMS where COMPONENTID in (select COMPONENTID from FLC_PAGE_COMPONENT where PAGEID = 31)) union select TRIGGER_BL from FLC_TRIGGER where TRIGGER_STATUS = 1 and TRIGGER_TYPE = 'JS' and TRIGGER_ITEM_TYPE = 'control' and TRIGGER_ITEM_ID in (select CONTROLID from FLC_PAGE_CONTROL where PAGEID = 31) ) a ) and BLPARENT is null