1、格式
update table_a a
left join table_b b
on a.id = b.biz_id
set a.name = b.name
where a.name = 'hg'
说明1: 优先做左连接
说明2: on条件关联,可以有多个,多个用and连接
说明3: 赋值
说明4: where过滤
2、示例
update t_hg_demo_p p
left join t_hg_demo_t t
on p.sn = t.sn
and p.year = year(t.create_time)
and p.month = month(t.create_time)
and p.day = day(t.create_time)
and p.hour = date_format(t.create_time, '%H')
and p.minutes = date_format(t.create_time, '%i')
and p.seconds = date_format(t.create_time, '%s')
set p.inverter_out_vol = t.mppt_in_vol,p.inverter_out_ele = t.mppt_in_ele
where p.sn = 'hg001'
说明1: 根据时间关联更新另一张表