| SQL adaptation guide For PostgreSQL 8.x.y, 9.x.y / Database concepts | |
Until version 11.70.xC2, Informix® database users had to be created at the operating system level and be members of the 'informix' group. Starting with 11.70.xC2, Informix supports database-only users with the CREATE USER instruction, as in most other db servers. Any database user must have sufficient privileges to connect and use resources of the database; user rights are defined with the GRANT command.
PostgreSQL users must be registered in the database. They are created by the createuser utility:
$ createuser --username=username --password
Based on the application logic (is it a multiuser application ?), you have to create one or several PostgreSQL users.