NEXT Live SQL
In a query involving multiple tables, all columns must be explicitly specified and with aliases. If you use *, an error occurs:
select * from hr.regions r, hr.countries c
where r.region_id = c.region_id;
ORA-00918: REGION_ID: column ambiguously specified - appears in and
Columns:
select r.region_id r_id, c.region_id c_id
from hr.regions r, hr.countries c
where r.region_id = c.region_id;
R_ID C_ID
---- ----
20 20
40 40
10 10
20 20
20 20
10 10
30 30
10 10
IN “OLD” live SQL everything wors fine:
select * from hr.regions r, hr.countries c
where r.region_id = c.region_id;
