我的 COUNT(*) 在下面的查询中选择了表格 uses 中行数的计数,而不是在 距离 小于50的行数。
请告诉我为什么查询选择表格user 中的行数,而不是距离小于50的行数?
感谢提前。
SELECT COUNT(*), ( 6371 * ACOS( COS( RADIANS( 51.61050836267012 ) ) * COS( RADIANS( latitude ) ) * COS( RADIANS( longitude ) - RADIANS( - 0.23701071739196777 ) ) + SIN( RADIANS( 51.61050836267012 ) ) * SIN( RADIANS( latitude ) ) ) )
AS distance
FROM `users`
AS `u`
HAVING distance <=50
HAVING 应该与 GROUP by 表达式相关。 要将行数限制在特定标准下, 请使用 WHERE 距离 < = 50
HAVING works on aggregated values (such as sum(column) having a certain condition)
You should use WHERE instead of HAVING in your case
拥有条款时不会在行上过滤,就像对您的计数函数的条款一样。请尝试使用子查询代替 。
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