sql语句中的join有以下几种:
- inner join
- left outer join
- right outer join
- cross join
- 全外联合
-
inner join 等同于join 其运行结果如下图所示:
-
left outer join
-
right outer join
-
full outer join
-
where B.key=NULL
-
where A.key=null
2023-12-05 22:23:22
sql语句中的join有以下几种:
inner join 等同于join 其运行结果如下图所示:
left outer join
right outer join
full outer join
where B.key=NULL
where A.key=null
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