I’m not sure about what do want to accomplish, but the syntax for a full cartesian product(cross join) is select * from table1, table2
If you don’t want to cross everything but only some columns, something like
SELECT *
FROM (select id from details) b, (select detail from details) c
;
should work:
id detail
1 name
2 name
3 name
4 name
5 name
1 email
2 email
....
Hope this helps.