using

using等价于join操作中的on，然后匹配两张表的相同字段；
例如a和b根据id字段关联，那么以下等价
using(id) <-> on a.id=b.id
如以下2个实例等价：

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select a.name,b.age from t_1 as a join t_2 as b on a.id=b.id
等价于
select a.name,b.age from t_1 as a join t_2 as b using(id)

还可以根据多值相等，如

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select a.name,b.age from t_1 as a join t_2 as b on a.id=b.id and a.name=b.name
等价于
select a.name,b.age from t_1 as a join t_2 as b using(id,name)

with as

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with as temp_name_a(
    -- 这里就是查询回来一个临时表
    select col_a,col_b,col_c from a inner join b on a.id=b.id
)
selec * from temp_name_a

Mysql语法