join_table:
table_reference JOIN table_factor [join_condition]
| table_reference {LEFT|RIGHT|FULL} [OUTER] JOIN table_reference
join_condition
| table_reference LEFT SEMI JOIN table_reference join_condition
table_reference:
table_factor
| join_table
table_factor:
tbl_name [alias]
| table_subquery alias
| ( table_references )
join_condition:
ON equality_expression ( AND equality_expression )*
equality_expression:
expression = expression
Hive only support equality join.
2010/10/9 Neil Xu <neil.x...@gmail.com>
> In oracle,
>
> select a.str1,
> b.str2
> from ( select str1 from table1) a,
> ( select str2 from table2) b
> where instr(a.str1,a.str2) > 0
>
> I know that 'from a, b' is not supported in hive, but table1 and table2
> have no common keys, if 'join' is used, it will be a FULL OUTER JOIN,
> when table1 and table2 have large number of tuples, the task will probably
> fail
>
> so, is there any better way to do the job? Thanks in advance
>
>
> Neil
>
