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我试图显示一个特定城镇的行政区和邮政编码。

我的数据库结构相当好，有一个表格，例如城镇、邮政编码和自治市镇。每个关系 town_postcode 和 town_borough 也有表格。

理想情况下，我希望数据返回为：

“艾比伍德”、“SE2”、“贝克斯利、格林威治”、“巴比肯”、“EC1、EC2”、“伦敦金融城”

我尝试了几种不同的方法，我很接近但还没有。

任何帮助将不胜感激...... :) 到目前为止我已经尝试过

SELECT DISTINCT t.town, 
GROUP_CONCAT( DISTINCT p.postcode SEPARATOR ', ' ) AS 'postcode', 
GROUP_CONCAT( DISTINCT b.borough SEPARATOR ', ' ) AS 'borough'
FROM coverage_towns AS t, 
coverage_boroughs AS b, 
coverage_postcodes AS p, 
coverage_towns_boroughs AS tb, 
coverage_towns_postcodes AS tp
WHERE t.id = tp.town_id
AND p.id = tp.postcode_id
AND b.id = tb.borough_id
GROUP BY t.town
ORDER BY t.town ASC

哪个返回

"Abbey Wood", "SE2", "Southwark, Hammersmith and Fulham, Tower Hamlets, Wandsworth, Enfield, Newham, LOTS MORE HERE"
"Barbican", "EC1, EC2", "Brent, Greenwich, Kensington and Chelsea, Westminster, Camden, LOTS MORE HERE"

我也试过

SELECT DISTINCT t.town, (

SELECT SQL_CACHE DISTINCT GROUP_CONCAT( p1.postcode
SEPARATOR ', ' )
FROM coverage_postcodes AS p1
WHERE p1.id = tp.postcode_id
) AS 'postcode', (

SELECT SQL_CACHE DISTINCT GROUP_CONCAT( b1.borough
SEPARATOR ', ' )
FROM coverage_boroughs AS b1
WHERE b1.id = tb.borough_id
) AS 'borough'
FROM coverage_towns AS t, coverage_boroughs AS b, coverage_postcodes AS p, coverage_towns_boroughs AS tb, coverage_towns_postcodes AS tp
WHERE t.id = tp.town_id
AND p.id = tp.postcode_id
AND b.id = tb.borough_id
GROUP BY t.town
ORDER BY t.town ASC

哪个返回

"Abbey Wood", "SE2", "Greenwich"
"Acton", "W3", "Greenwich"
"Aldersbrook", "E12", "Greenwich"
4

2 回答 2

1

解决方案

喝了一杯好咖啡后，我回到了这个问题，答案就出来了。

SELECT DISTINCT t.town, 
GROUP_CONCAT( DISTINCT p.postcode SEPARATOR ', ' ) AS 'postcode', 
GROUP_CONCAT( DISTINCT b.borough SEPARATOR ', ' ) AS 'borough'
FROM towns AS t, boroughs AS b, postcodes AS p, towns_boroughs AS tb, towns_postcodes AS tp
WHERE (t.id = tp.town_id AND t.id = tb.town_id)
AND (p.id = tp.postcode_id AND b.id = tb.borough_id)
GROUP BY t.town
ORDER BY t.town ASC
于 2010-10-21T15:06:33.770 回答
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第一个查询看起来不错，只需在distinct中添加group_concat，例如：

SELECT  t.town
,      GROUP_CONCAT(DISTINCT p.postcode SEPARATOR ', ' ) AS 'postcode'
,      GROUP_CONCAT(DISTINCT b.borough SEPARATOR ', ' ) AS 'borough'
<more code here>
GROUP BY
        t.town
于 2010-10-21T12:30:56.607 回答