我想要的是:
- 用户传入邮政编码或城市名称
- 我在数据库中搜索 5 个最近的地点
- 显示距离用户最近的 5 个位置
到目前为止我所拥有的:
假设有一个包含以下内容的地点表:
(about 16000 rows)
CREATE TABLE `locations` (
`locationID` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(150) NOT NULL,
`firstname` varchar(100) DEFAULT NULL,
`lastname` varchar(100) DEFAULT NULL,
`street` varchar(100) NOT NULL,
`city` varchar(100) NOT NULL,
`state` varchar(100) NOT NULL,
`zipcode` varchar(10) NOT NULL,
`phone` varchar(20) NOT NULL,
`web` varchar(255) DEFAULT NULL,
`machine` enum('Unbekannt','Foo','Bar') DEFAULT 'Unbekannt',
`surface` enum('Unbekannt','Foo','Bar','') DEFAULT 'Unbekannt',
PRIMARY KEY (`locationID`)
) ENGINE=InnoDB AUTO_INCREMENT=25 DEFAULT CHARSET=utf8
- ID
- name
- zip code
- city
现在我有了第二张表,其中包含世界上所有的城镇:
(about 340万 rows)
CREATE TABLE `geoData` (
`geoID` int(11) NOT NULL AUTO_INCREMENT,
`countryCode` char(2) NOT NULL,
`zipCode` varchar(20) NOT NULL,
`name` varchar(180) NOT NULL,
`state` varchar(100) NOT NULL,
`stateCode` varchar(20) NOT NULL,
`county` varchar(100) NOT NULL,
`countyCode` varchar(20) NOT NULL,
`community` varchar(100) NOT NULL,
`communityCode` varchar(20) NOT NULL,
`lat` mediumint(6) NOT NULL,
`lon` mediumint(6) NOT NULL,
PRIMARY KEY (`lon`,`lat`,`geoID`) USING BTREE,
KEY `geoID` (`geoID`)
) ENGINE=InnoDB AUTO_INCREMENT=16482 DEFAULT CHARSET=utf8
/*!50100 PARTITION BY RANGE (lat)
(PARTITION p0 VALUES LESS THAN (-880000) ENGINE = InnoDB,
PARTITION p1 VALUES LESS THAN (-860000) ENGINE = InnoDB,
PARTITION p2 VALUES LESS THAN (-840000) ENGINE = InnoDB,
PARTITION p3 VALUES LESS THAN (-820000) ENGINE = InnoDB,
PARTITION p4 VALUES LESS THAN (-800000) ENGINE = InnoDB,
PARTITION p5 VALUES LESS THAN (-780000) ENGINE = InnoDB,
PARTITION p6 VALUES LESS THAN (-760000) ENGINE = InnoDB,
PARTITION p7 VALUES LESS THAN (-740000) ENGINE = InnoDB,
PARTITION p8 VALUES LESS THAN (-720000) ENGINE = InnoDB,
PARTITION p9 VALUES LESS THAN (-700000) ENGINE = InnoDB,
PARTITION p10 VALUES LESS THAN (-680000) ENGINE = InnoDB,
PARTITION p11 VALUES LESS THAN (-660000) ENGINE = InnoDB,
PARTITION p12 VALUES LESS THAN (-640000) ENGINE = InnoDB,
PARTITION p13 VALUES LESS THAN (-620000) ENGINE = InnoDB,
PARTITION p14 VALUES LESS THAN (-600000) ENGINE = InnoDB,
PARTITION p15 VALUES LESS THAN (-580000) ENGINE = InnoDB,
PARTITION p16 VALUES LESS THAN (-560000) ENGINE = InnoDB,
PARTITION p17 VALUES LESS THAN (-540000) ENGINE = InnoDB,
PARTITION p18 VALUES LESS THAN (-520000) ENGINE = InnoDB,
PARTITION p19 VALUES LESS THAN (-500000) ENGINE = InnoDB,
PARTITION p20 VALUES LESS THAN (-480000) ENGINE = InnoDB,
PARTITION p21 VALUES LESS THAN (-460000) ENGINE = InnoDB,
PARTITION p22 VALUES LESS THAN (-440000) ENGINE = InnoDB,
PARTITION p23 VALUES LESS THAN (-420000) ENGINE = InnoDB,
PARTITION p24 VALUES LESS THAN (-400000) ENGINE = InnoDB,
PARTITION p25 VALUES LESS THAN (-380000) ENGINE = InnoDB,
PARTITION p26 VALUES LESS THAN (-360000) ENGINE = InnoDB,
PARTITION p27 VALUES LESS THAN (-340000) ENGINE = InnoDB,
PARTITION p28 VALUES LESS THAN (-320000) ENGINE = InnoDB,
PARTITION p29 VALUES LESS THAN (-300000) ENGINE = InnoDB,
PARTITION p30 VALUES LESS THAN (-280000) ENGINE = InnoDB,
PARTITION p31 VALUES LESS THAN (-260000) ENGINE = InnoDB,
PARTITION p32 VALUES LESS THAN (-240000) ENGINE = InnoDB,
PARTITION p33 VALUES LESS THAN (-220000) ENGINE = InnoDB,
PARTITION p34 VALUES LESS THAN (-200000) ENGINE = InnoDB,
PARTITION p35 VALUES LESS THAN (-180000) ENGINE = InnoDB,
PARTITION p36 VALUES LESS THAN (-160000) ENGINE = InnoDB,
PARTITION p37 VALUES LESS THAN (-140000) ENGINE = InnoDB,
PARTITION p38 VALUES LESS THAN (-120000) ENGINE = InnoDB,
PARTITION p39 VALUES LESS THAN (-100000) ENGINE = InnoDB,
PARTITION p40 VALUES LESS THAN (-80000) ENGINE = InnoDB,
PARTITION p41 VALUES LESS THAN (-60000) ENGINE = InnoDB,
PARTITION p42 VALUES LESS THAN (-40000) ENGINE = InnoDB,
PARTITION p43 VALUES LESS THAN (-20000) ENGINE = InnoDB,
PARTITION p44 VALUES LESS THAN (0) ENGINE = InnoDB,
PARTITION p45 VALUES LESS THAN (20000) ENGINE = InnoDB,
PARTITION p46 VALUES LESS THAN (40000) ENGINE = InnoDB,
PARTITION p47 VALUES LESS THAN (60000) ENGINE = InnoDB,
PARTITION p48 VALUES LESS THAN (80000) ENGINE = InnoDB,
PARTITION p49 VALUES LESS THAN (100000) ENGINE = InnoDB,
PARTITION p50 VALUES LESS THAN (120000) ENGINE = InnoDB,
PARTITION p51 VALUES LESS THAN (140000) ENGINE = InnoDB,
PARTITION p52 VALUES LESS THAN (160000) ENGINE = InnoDB,
PARTITION p53 VALUES LESS THAN (180000) ENGINE = InnoDB,
PARTITION p54 VALUES LESS THAN (200000) ENGINE = InnoDB,
PARTITION p55 VALUES LESS THAN (220000) ENGINE = InnoDB,
PARTITION p56 VALUES LESS THAN (240000) ENGINE = InnoDB,
PARTITION p57 VALUES LESS THAN (260000) ENGINE = InnoDB,
PARTITION p58 VALUES LESS THAN (280000) ENGINE = InnoDB,
PARTITION p59 VALUES LESS THAN (300000) ENGINE = InnoDB,
PARTITION p60 VALUES LESS THAN (320000) ENGINE = InnoDB,
PARTITION p61 VALUES LESS THAN (340000) ENGINE = InnoDB,
PARTITION p62 VALUES LESS THAN (360000) ENGINE = InnoDB,
PARTITION p63 VALUES LESS THAN (380000) ENGINE = InnoDB,
PARTITION p64 VALUES LESS THAN (400000) ENGINE = InnoDB,
PARTITION p65 VALUES LESS THAN (420000) ENGINE = InnoDB,
PARTITION p66 VALUES LESS THAN (440000) ENGINE = InnoDB,
PARTITION p67 VALUES LESS THAN (460000) ENGINE = InnoDB,
PARTITION p68 VALUES LESS THAN (480000) ENGINE = InnoDB,
PARTITION p69 VALUES LESS THAN (500000) ENGINE = InnoDB,
PARTITION p70 VALUES LESS THAN (520000) ENGINE = InnoDB,
PARTITION p71 VALUES LESS THAN (540000) ENGINE = InnoDB,
PARTITION p72 VALUES LESS THAN (560000) ENGINE = InnoDB,
PARTITION p73 VALUES LESS THAN (580000) ENGINE = InnoDB,
PARTITION p74 VALUES LESS THAN (600000) ENGINE = InnoDB,
PARTITION p75 VALUES LESS THAN (620000) ENGINE = InnoDB,
PARTITION p76 VALUES LESS THAN (640000) ENGINE = InnoDB,
PARTITION p77 VALUES LESS THAN (660000) ENGINE = InnoDB,
PARTITION p78 VALUES LESS THAN (680000) ENGINE = InnoDB,
PARTITION p79 VALUES LESS THAN (700000) ENGINE = InnoDB,
PARTITION p80 VALUES LESS THAN (720000) ENGINE = InnoDB,
PARTITION p81 VALUES LESS THAN (740000) ENGINE = InnoDB,
PARTITION p82 VALUES LESS THAN (760000) ENGINE = InnoDB,
PARTITION p83 VALUES LESS THAN (780000) ENGINE = InnoDB,
PARTITION p84 VALUES LESS THAN (800000) ENGINE = InnoDB,
PARTITION p85 VALUES LESS THAN (820000) ENGINE = InnoDB,
PARTITION p86 VALUES LESS THAN (840000) ENGINE = InnoDB,
PARTITION p87 VALUES LESS THAN (860000) ENGINE = InnoDB,
PARTITION p88 VALUES LESS THAN (880000) ENGINE = InnoDB,
PARTITION p89 VALUES LESS THAN MAXVALUE ENGINE = InnoDB) */
- ID
- city
- zip code
- latitude
- 经度
基于此article http://mysql.rjweb.org/doc.php/latlng#representation_choices和其他一些关于此事的阅读我有一个存储过程,它给了我n靠近某个点(纬度/经度)的最近城镇的位置/邮政编码。
我的存储过程:
BEGIN
DECLARE _deg2rad DOUBLE DEFAULT PI()/1800000;
SET @my_lat := _my_lat,
@my_lon := _my_lon,
@deg2dist := 0.0111325,
@start_deg := _start_dist / @deg2dist,
@max_deg := _max_dist / @deg2dist,
@cutoff := @max_deg / SQRT(2),
@dlat := @start_deg,
@lon2lat := COS(_deg2rad * @my_lat),
@iterations := 0;
SET @sql = CONCAT(
"SELECT COUNT(*) INTO @near_ct
FROM geoData
WHERE lat BETWEEN @my_lat - @dlat
AND @my_lat + @dlat
AND lon BETWEEN @my_lon - @dlon
AND @my_lon + @dlon");
PREPARE _sql FROM @sql;
MainLoop: LOOP
SET @iterations := @iterations + 1;
SET @dlon := ABS(@dlat / @lon2lat);
SET @dlon := IF(ABS(@my_lat) + @dlat >= 900000, 3600001, @dlon);
EXECUTE _sql;
IF ( @near_ct >= _limit OR
@dlat >= @cutoff ) THEN
LEAVE MainLoop;
END IF;
SET @dlat := LEAST(2 * @dlat, @cutoff);
END LOOP MainLoop;
DEALLOCATE PREPARE _sql;
SET @dlat := IF( @dlat >= @max_deg OR @dlon >= 1800000,
@max_deg,
GCDist(ABS(@my_lat), @my_lon,
ABS(@my_lat) - @dlat, @my_lon - @dlon) );
SET @dlon := IFNULL(ASIN(SIN(_deg2rad * @dlat) /
COS(_deg2rad * @my_lat))
/ _deg2rad
, 3600001);
IF (ABS(@my_lon) + @dlon < 1800000 OR
ABS(@my_lat) + @dlat < 900000) THEN
SET @sql = CONCAT(
"SELECT *,
@deg2dist * GCDist(@my_lat, @my_lon, lat, lon) AS dist
FROM geoData
WHERE lat BETWEEN @my_lat - @dlat
AND @my_lat + @dlat
AND lon BETWEEN @my_lon - @dlon
AND @my_lon + @dlon
HAVING dist <= ", _max_dist, "
ORDER BY dist
LIMIT ", _limit
);
ELSE
SET @west_lon := IF(@my_lon < 0, @my_lon, @my_lon - 3600000);
SET @east_lon := @west_lon + 3600000;
SET @sql = CONCAT(
"( SELECT *,
@deg2dist * GCDist(@my_lat, @west_lon, lat, lon) AS dist
FROM geoData
WHERE lat BETWEEN @my_lat - @dlat
AND @my_lat + @dlat
AND lon BETWEEN @west_lon - @dlon
AND @west_lon + @dlon
HAVING dist <= ", _max_dist, " )
UNION ALL
( SELECT *,
@deg2dist * GCDist(@my_lat, @east_lon, lat, lon) AS dist
FROM geoData
WHERE lat BETWEEN @my_lat - @dlat
AND @my_lat + @dlat
AND lon BETWEEN @east_lon - @dlon
AND @east_lon + @dlon
HAVING dist <= ", _max_dist, " )
ORDER BY dist
LIMIT ", _limit
);
END IF;
PREPARE _sql FROM @sql;
EXECUTE _sql;
DEALLOCATE PREPARE _sql;
END
我的问题:
我想传递邮政编码或城镇名称,然后从那里开始搜索。所以我的想法是我请求这些信息并查找世界上所有城镇/邮政编码的表格。之后,如果只找到一个结果,我就会获得纬度/经度信息,或者在有多个结果的情况下我会要求用户选择正确的选择。
之后,我开始搜索离我当前位置最近的城镇。假设我想要 50 个城镇/城市的列表。然后,我会去查找包含位置的表是否与其中的 5 个结果匹配。
转念一想,这听起来是个坏主意......
方法一:
我阅读了存储过程、sql 和怪物查询,并尝试得到以下内容:
传递一个邮政编码/城市名称,我会查找它,从巨大的表中取出我的纬度/经度(可能是mysql中的函数),有了这个,我会寻找最近的城镇,然后立即加入位置表并获取我最近的 5 个位置。
问题:
- 如何避免城市/邮政编码的同名出现多个匹配项?
- 听起来是否可以通过简单的连接来获得 5 个最近的位置?
方法2:
获取我所在位置的所有纬度/经度值,然后在此表上运行该过程。然后只使用巨大的表来检索我当前的位置?
这样,我就需要收集我所在位置的所有纬度/经度。但这可能是最好的方法。
但是,仅仅为了获取位置而拥有所有城市/邮政编码的庞大数据库似乎有点大材小用。我希望有一个替代方案,然后也许......不知何故......
方法3
说实话,我想要的这个函数好像已经写了一百万遍了。那么我为什么要费心重新发明轮子呢?但我不知道如何找到合适的文章或书籍来实现我的目标。
你们中还有其他人有关于类似事情的最佳实践的想法吗?