Question

我的SQL查询工作正常，直到我尝试添加'WHERE距离＆lt;分别在第4行和第10行的10'和'计算块AS距离'。知道如何解决它吗？谢谢！

Unknown column 'distance' in 'where clause'

SELECT SQL_CALC_FOUND_ROWS places.*, category.*, 
COUNT(places_reviews.place_id) AS num_reviews, 
(places_popularity.rating_1 + 2*places_popularity.rating_2 + 3*places_popularity.rating_3 + 4*places_popularity.rating_4 + 5*places_popularity.rating_5)/(places_popularity.rating_1 + places_popularity.rating_2 + places_popularity.rating_3 + places_popularity.rating_4 + places_popularity.rating_5) AS average_rating, 
6371 * acos( cos( radians(places.lat) ) * cos( radians( 1.29315 ) ) * cos( radians( 103.827164 ) - radians(places.lng) ) + sin( radians(places.lat) ) * sin( radians( 1.29315 ) ) ) AS distance 
FROM (places) 
JOIN category 
ON places.category_id = category.category_id 
LEFT JOIN places_reviews ON places_reviews.place_id = places.id 
LEFT JOIN places_popularity ON places_popularity.place_id = places.id 
WHERE `places`.`category_id` = 1 AND `distance` < 5 AND places.name LIKE '%%' GROUP 
BY places.id 
ORDER BY id desc 
LIMIT 5

Answer 1

您需要将公式放在WHERE子句中，而不是使用别名距离。在SQL查询中，WHERE子句在SELECT语句之前计算，因此别名（在本例中为distance）尚不存在。这是您的SQL语句的样子：

SELECT SQL_CALC_FOUND_ROWS places.*, category.*, 
COUNT(places_reviews.place_id) AS num_reviews, 
(places_popularity.rating_1 + 2*places_popularity.rating_2 + 3*places_popularity.rating_3 + 4*places_popularity.rating_4 + 5*places_popularity.rating_5)/(places_popularity.rating_1 + places_popularity.rating_2 + places_popularity.rating_3 + places_popularity.rating_4 + places_popularity.rating_5) AS average_rating, 
6371 * acos( cos( radians(places.lat) ) * cos( radians( 1.29315 ) ) * cos( radians( 103.827164 ) - radians(places.lng) ) + sin( radians(places.lat) ) * sin( radians( 1.29315 ) ) ) AS distance 
FROM (places) 
JOIN category 
ON places.category_id = category.category_id 
LEFT JOIN places_reviews ON places_reviews.place_id = places.id 
LEFT JOIN places_popularity ON places_popularity.place_id = places.id 
WHERE `places`.`category_id` = 1 
   AND (6371 * acos( cos( radians(places.lat) ) * cos( radians( 1.29315 ) ) * cos( radians( 103.827164 ) - radians(places.lng) ) + sin( radians(places.lat) ) * sin( radians( 1.29315 ) ) )) < 5
   AND places.name LIKE '%%' GROUP 
BY places.id 
ORDER BY id desc 
LIMIT 5

您可以通过名称引用distance的唯一方法是将您的语句包装并将其放入新SELECT语句中的表中。例如：

SELECT *
FROM ( <insert your original query here without the WHERE distance= statement ) AS t
WHERE distance < 5

这个mySQL查询有问题:(使用带有AS子句的WHERE）

1 个答案: