添加LEFT JOIN後破碎的計數（*）

Question

由於將LEFT JOIN添加到下面的查詢中，count（*）返回了一些奇怪的值，它似乎已將查詢中返回的總行添加到'level '：

SELECT `n`.*, exp_channel_titles.*, round((`n`.`rgt` - `n`.`lft` - 1)/2, 0) AS childs, 
count(*) - 1 + (`n`.`lft` > 1) + 1 AS level, 
((min(`p`.`rgt`) - `n`.`rgt` - (`n`.`lft` > 1))/2) > 0 AS lower, 
(((`n`.`lft` - max(`p`.`lft`) > 1))) AS upper 
FROM `exp_node_tree_6` `n` 
    LEFT JOIN `exp_channel_titles` 
    ON (`n`.`entry_id`=`exp_channel_titles`.`entry_id`), 
    `exp_node_tree_6` `p`, 
    `exp_node_tree_6` 
WHERE `n`.`lft` 
BETWEEN `p`.`lft` 
AND `p`.`rgt` 
AND (`p`.`node_id` != `n`.`node_id` OR `n`.`lft` = 1) 
GROUP BY `n`.`node_id` 
ORDER BY `n`.`lft` 

我完全難住...謝謝！

Answer 1

如果您想知道計數，只需運行沒有group by的查詢即可。你會看到計數中的行來自哪裏。你可以修改count(*)到count distinct(n.entry_id)。