To find out the current schema that we are connect to, we may use function sys_context(). I connected to Oracle SQL Live at https://livesql.oracle.com and ran the following query:
select sys_context('USERENV', 'SESSION_USER') from dual;
SYS_CONTEXT('USERENV','SESSION_USER')
APEX_PUBLIC_USER
The returned result showed that the schema name was APEX_PUBLIC_USER.
