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我有一個存儲過程，它根據用戶可以選擇多個要搜索的位置的事實來查找用戶的首選項。因此，對於每個位置，查詢都需要查找結果該地區。目前，該過程只返回1個結果。另外，我希望能夠實施某種排名系統，以便將結果排序爲一個組合Feed。我意識到，如果我使用的是一個while循環，它將按位置對結果進行分組，這是我不想要的。重構此過程的最佳方法是什麼，以便3個查詢的結果是網狀的，並允許我靈活地對結果進行排序？結合MySQL存儲過程的結果
DELIMITER $$
DROP PROCEDURE IF EXISTS `geodist` $$
CREATE PROCEDURE geodist (IN userid INT) BEGIN
DECLARE mylon DOUBLE; DECLARE mylat DOUBLE;
DECLARE lon1 FLOAT; DECLARE lon2 FLOAT;
DECLARE lat1 FLOAT; DECLARE lat2 FLOAT;
DECLARE dist INT;
DECLARE no_more_locations INT; DECLARE l_location_count INT;
-- get the original lon and lat for the userid
DECLARE location_cursor CURSOR FOR
SELECT geo_lat, geo_long, distance
FROM activity_location_preferences
INNER JOIN activity_preferences ON activity_location_preferences.preference_id = activity_preferences.id
WHERE activity_preferences.user_id = userid
ORDER BY activity_preferences.id ASC
LIMIT 3;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET no_more_locations = 1;
SET no_more_locations = 0;
OPEN location_cursor;
location_loop:WHILE(no_more_locations = 0) DO
FETCH location_cursor INTO mylat, mylon, dist;
IF no_more_locations = 1 THEN
LEAVE location_loop;
END IF;
SET l_location_count = l_location_count+1;
-- calculate lon and lat for the rectangle:
SET lon1 = mylon - dist/abs(cos(radians(mylat)) * 69);
SET lon2 = mylon + dist/abs(cos(radians(mylat)) * 69);
SET lat1 = mylat - (dist/69);
SET lat2 = mylat + (dist/69);
-- run the query:
SELECT `id`, `user_id`, `activity`, `geo_lat`, `geo_long`, `data`, `date_created`,
7912 * ASIN(SQRT(POWER(SIN((mylat - activity_logs.geo_lat) * pi()/180/2), 2) +
COS(mylat * pi()/180) * COS(activity_logs.geo_lat * pi()/180) * POWER(SIN((mylon - activity_logs.geo_long) * pi()/180/2), 2) )) as distance
FROM activity_logs
WHERE 1
AND activity_logs.geo_long BETWEEN lon1 AND lon2
AND activity_logs.geo_lat BETWEEN lat1 AND lat2
HAVING distance < dist ORDER BY date_created DESC LIMIT 100;
END WHILE location_loop;
CLOSE location_cursor;
SET no_more_locations = 0;
END $$
DELIMITER ;