https://www.cnblogs.com/wkrbky/p/5882975.html
SQL各种连接查询详解(左连接、右连接..)
https://blog.youkuaiyun.com/yueqi1125/article/details/79478143
SQL查询:并集、差集、交集
https://blog.youkuaiyun.com/weixin_41852491/article/details/80496998
HIVE当中的关联查询
https://blog.youkuaiyun.com/SONGCHUNHONG/article/details/78887326
hive的6种join操作
https://blog.youkuaiyun.com/u012965373/article/details/80518345
Hive 中HQL中inner join,join, left join,full join区别
https://blog.youkuaiyun.com/smile0198/article/details/38665321
hive 各种 join (left outer join、join、full outer join)
https://blog.youkuaiyun.com/smile0198/article/details/40051325
hive union all 使用
https://blog.youkuaiyun.com/lu0422/article/details/78892497
Mysql中的关联查询(内连接,外连接,自连接)
https://blog.youkuaiyun.com/plg17/article/details/78758593