MYSQL FROM多表多JOIN

Question

我的 SQL 代码:

SELECT
    *
FROM
    map_features_stations,
    map_fuels_stations
RIGHT JOIN fuelprices ON fuelprices.fuel_id = map_fuels_stations.fuel_id
RIGHT JOIN map_stations ON map_fuels_stations.station_id = map_stations.id
RIGHT JOIN map_locations ON map_stations.location_id = map_locations.id
RIGHT JOIN map_features ON map_features.id = map_features_stations.feature_id

我有错误 [Err] 1054 - “on 子句”中的未知列“feat.feature_id”

我的 map_features_stations 表中有这一列。

SELECT * FROM map_features_stations
INNER JOIN map_features ON map_features.id = map_features_stations.feature_id

这很好用...

谁能帮帮我？

---

更新

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SELECT
    GROUP_CONCAT(DISTINCT CONCAT(map_features.id, '-', map_features.name_eng)) AS 'existingFeatures',
    GROUP_CONCAT(DISTINCT map_features_stations.feature_id) AS 'allFeatures',
    GROUP_CONCAT(DISTINCT map_fuels_stations.fuel_id) AS 'existingFuels',
    GROUP_CONCAT(DISTINCT CONCAT(fuelprices.fueL_id, '-', fuelprices.fuel_name)) AS 'allFeatures'

    FROM map_fuels_stations
    LEFT JOIN fuelprices ON fuelprices.fuel_id = map_fuels_stations.fuel_id
    LEFT JOIN map_stations ON map_fuels_stations.station_id = map_stations.id

    RIGHT JOIN map_locations ON map_stations.location_id = map_locations.id

    RIGHT JOIN map_features_stations ON map_features_stations.station_id = map_stations.id
    RIGHT JOIN map_features ON map_features_stations.feature_id = map_features.id

    GROUP BY map_stations.id
    HAVING map_stations.id = 1

我改了。结果是:

在现有(existingGeatures 和 existingFuels)列中，一切都很好。但是我怎样才能使 allFeatures 和 allFuels 列中的所有特征和所有燃料都在数据库中？

Answer 1

不要混合隐式和显式连接语法。在查询中的任何地方使用显式连接

SELECT
    *
FROM
    map_features_stations
JOIN map_fuels_stations on ...
RIGHT JOIN fuelprices ON fuelprices.fuel_id = map_fuels_stations.fuel_id
RIGHT JOIN map_stations ON map_fuels_stations.station_id = map_stations.id
RIGHT JOIN map_locations ON map_stations.location_id = map_locations.id
RIGHT JOIN map_features ON map_features.id = map_features_stations.feature_id