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hivEsql为什么有的字段不支持子查询

select * from (select no,name from 用户表)a left join 职务表 b on a.no=b.no

必须可以,hive支持子查询,子查询后边必须跟一个别名,例如下边的那个A select A.name from ( select name from test where col=123 ) A

使用MIN,MAX扫描,并且子查询走索引,逻辑读11,虽然不及前2个,但是还不错,并且SQL简单 dingjun123@ORADB> SELECT * FROM t 2 WHERE t.object_id IN 3 (SELECT MIN(object_id) FROM t UNION ALL 4 SELECT MAX(object_id) FROM t); 2 rows sele...

hive多表查询的条件写在join里好还是用子查询? 两个表关联查询,是把条件都写join on里好? select a.* from a join b on ( a.id = b.id and a.a = 2 and b.c = 3) 还是写成子查询的形式比较快? select a.* from a join (select b.* from b wh...

hive多表查询的条件写在join里好还是用子查询? 两个表关联查询,是把条件都写join on里好? select a.* from a join b on ( a.id = b.id and a.a = 2 and b.c = 3) 还是写成子查询的形式比较快? select a.* from a join (select b.* from b wh...

使用MIN,MAX扫描,并且子查询走索引,逻辑读11,虽然不及前2个,但是还不错,并且SQL简单 dingjun123@ORADB> SELECT * FROM t 2 WHERE t.object_id IN 3 (SELECT MIN(object_id) FROM t UNION ALL 4 SELECT MAX(object_id) FROM t); 2 rows sele...

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