左聯接，左表上帶有where子句

Question

我想過濾兩個給定日期之間的SQL結果，同時還要根據條件加入表。 這是我當前正在使用的SQL：

select
   event.location,
   event.dt,
   event.start
from event
where
   event.dt BETWEEN "2014-02-01" AND "2014-02-04"
   left join entity on entity.id = event.entity
   order by dt desc;

如果我將event.dt BETWEEN移到event.dt BETWEEN （即，在entity.id = . . . and event.dt BETWEEN ），它似乎根本無法過濾結果，從而使我在指定的日期范圍。

Answer 1

嘗試像這樣使用聯接

select  event.location, 
        event.dt, 
        event.start 
from    event left join 
        entity on entity.id = event.entity
where   event.dt BETWEEN "2014-02-01" AND "2014-02-04" 
order by dt desc;

Answer 2

您的查詢應如下所示

select
   event.location,
   event.dt,
   event.start
from event
   left join entity on entity.id = event.entity
where
   event.dt BETWEEN "2014-02-01" AND "2014-02-04"
   order by event.dt desc;