select 需要的字段用a.xx的形式写 from
a表 as a left join
b表 as b on a.xx=b.xx left join
c表 as c on b.xx=c.xx
where 后面就看自己的情况加判断;
时间: 2024-08-25 18:43:34
select 需要的字段用a.xx的形式写 from
a表 as a left join
b表 as b on a.xx=b.xx left join
c表 as c on b.xx=c.xx
where 后面就看自己的情况加判断;