Among the stores in weather station 14 in February 2014, which store had sold no less than 300 quantities for item number 44 in a single day?
weather station 14 refers to station_nbr = 14; February 2014 refers to substring (date, 1, 7) = '2014-02' ; sold no less than 300 quantities refers to units > = 300; item no.44 refers to item_nbr = 44; store refers to store_nbr
SELECT T1.store_nbr FROM sales_in_weather AS T1 INNER JOIN relation AS T2 ON T1.store_nbr = T2.store_nbr WHERE T2.station_nbr = 14 AND T1.`date` LIKE '%2014-02%' AND T1.item_nbr = 44 AND units >= 300