mysql - 如何将where子句变量放在选择查询的第一层

把select变量放在最近的查询层中，我在查询中失去了选择权。
从此行获取此错误unknown column h.date
我知道原因，因为我把gb.startTime = h.date放在左连接选择中。我认为这是安排上的问题。
有人知道吗？
这是我的问题：

set @maxBat = 10000;
set @minBat = 0;
select
    h.date,
    (select
        count(*)
    from(
        select
            distinct d.id,
            d.reg,
            ifnull(bc.battleCount, 0) AS battles
        from (
            select
                ds.id as id,
                ds.reg as reg
            ...
            ) as d
        left join
            (
            select
                count(gb.id) as battleCount,
                gb.playerID
            from g_battles as gb
            where
                gb.startTime = h.date
            group by gb.playerID
            ) as bc on bc.playerID = d.id
        having battles between @minBat and @maxBat
        ) as e
            where e.reg = h.date
    ) as regbattle
from
    sessiontable as h
where
...

最佳答案

您可以只在一个级别的back子查询中使用外部数据查询，而不是更多，例如，
没关系的

select id,(select count(index_)
from (select index_ from log_sops) as t where t.index_ = h.version)
from data_sops as h where id = 4

但这是错的

select id,(select count(index_)
from (select index_ from log_sops where id = h.version)
as t)
from data_sops as h where id = 4

关于mysql - 如何将where子句变量放在选择查询的第一层，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/55619043/