Data

The data below is used in the explicit and implicit example

And we want:

ID_table1  ID_table2
---------- ----------
A          A
A          B
A          C
B          A
B          B
B          C
D          A
D          B
D          C

9 rows selected.

We have 3 rows from table1 to multiply by 3 rows in the table2.

Real example of cross-join in this article : OWB - How to load a fact table for a data quality cube ?

Explicit

SELECT
	  table1.id "ID_table1"
	, table2.id "ID_table2"
	FROM
	  table1
	  CROSS JOIN table2;

Implicit

• There is no join condition

select table1.id "ID_table1", table2.id "ID_table2"
from table1, table2

• in case of when the application controls that you have set a join condition, you can add the 1=1 predicate.

select table1.id "ID_table1", table2.id "ID_table2"
from table1, table2
where 1=1;