不同于复杂的sql查询

Question

我还有一个给你们。我已经搜索过，但我无法弄清楚这个问题的原因。

基本上，我想对user_id做一个DISTINCT，它是一个自然加入并存在于表“user”和“leaderboard_entry”中的列。

这是我的原始查询，它的效果很好，但我想过滤出重复项，并只显示第一个最快的用户分数。内部查询基本上抓取了最近的100行，而外部查询通过升序leaderboard_entry_elapsed_time_ms来衡量它们。 “leaderboard_entry *，”

set @t1=0; select * from 
( 
    select @t1 := @t1+1 as leaderboard_entry_youngness_rank, 1-@t1/100 as 
    leaderboard_entry_youngness_based_on_expiry, 
    leaderboard_entry.*, 
    NOW()-leaderboard_entry_timestamp as leaderboard_entry_age_in_some_units , 
    TO_DAYS(NOW())-TO_DAYS(leaderboard_entry_timestamp) 
    as leaderboard_entry_age_in_days , leaderboard.leaderboard_quiz_mode , 
    leaderboard.leaderboard_load_key , 
    user.user_name 
    from leaderboard_entry 
    natural join 
    leaderboard 
    natural join 
    user 
    where 
    (leaderboard_load_key = 'es-en-animals-1' 
    or leaderboard_load_key = '-es-en-animals-1') 
    and leaderboard_quiz_mode = '0' 
    order by leaderboard_entry_age_in_some_units asc , 
    leaderboard_entry_timestamp asc limit 0, 100 
) as outer_temp 
order by 
    leaderboard_entry_elapsed_time_ms asc , 
    leaderboard_entry_timestamp asc 
limit 0, 50 

我试过以下，这是去除与列的明确命名添加DISTINCT关键字一样，所以我需要：

set @t1=0; select * from 
( 
    select @t1 := @t1+1 as leaderboard_entry_youngness_rank, 1-@t1/100 as 
    leaderboard_entry_youngness_based_on_expiry,
 

NOW()-leaderboard_entry_timestamp as leaderboard_entry_age_in_some_units , TO_DAYS(NOW())-TO_DAYS(leaderboard_entry_timestamp) as leaderboard_entry_age_in_days , leaderboard.leaderboard_quiz_mode , leaderboard.leaderboard_load_key , user.user_name
 

distinct leaderboard_entry.user_id, leaderboard_entry.leaderboard_entry_id, leaderboard_entry.leaderboard_id, leaderboard_entry.leaderboard_entry_timestamp, leaderboard_entry.leaderboard_entry_elapsed_time_ms,
 

from leaderboard_entry natural join leaderboard natural join user where (leaderboard_load_key = 'es-en-animals-1' or leaderboard_load_key = '-es-en-animals-1') and leaderboard_quiz_mode = '0' order by leaderboard_entry_age_in_some_units asc , leaderboard_entry_timestamp asc limit 0, 100 ) as outer_temp order by leaderboard_entry_elapsed_time_ms asc , leaderboard_entry_timestamp asc limit 0, 50 

，但我得到这个错误，它没有任何意义... :(

#1064 - You have an error in your SQL syntax; 
check the manual that corresponds to your MySQL 
server version for the right syntax to use near 
'distinct leaderboard_entry.user_id, leaderboard_entry.leaderboard_entry_id, ' 
at line 12 

任何帮助，非常感谢！ 猪

Answer 1

通过上面的Scrum Meister回答