You need to create new user in Oracle database with ability to connect and manage data objects
The simplest form is:
create user ecxtenant102 identified by ecxtenant102_secret
where ecxtenant102_secret is user's password
For more comprehensive explanation, please refer to http://www.stanford.edu/dept/itss/docs/oracle/10g/server.101/b10759/statements_8003.htm
I also had to assign two roles to that user.
grant connect, resource to ecxtenant102