PostgreSQL Security/Roles/Grants

Hi,<br /><br />I come from an Oracle background and wonder if anyone could provide some background information on how
bestto implement an application security scheme in PostgreSQL using roles / grants.<br /><br />I'd just like to outline
firsthow I'd approach security in Oracle:<br /><br />There is a notion of both:<br /><br />1. Default Roles -> a
rolewhich is activated at login time. Oracle imposes a limit on the number of default roles which any given user can
have.<br/><br />2. Non-default role -> a role which has to be explicitly activated during the lifecycle of an
applicationin order to gain access to database resources. There are no limits on the number of non-default roles. This
typeof role helps us to only provide a user with the minimal set of privileges that they require at any given time, and
minimisetheir access to database resources.<br /><br />I have looked through the PostgreSQL documentation, and cannot
findanything analogous to the 'non-default role' which I have outlined above - although obviously it does support
roles.<br/><br />I just want to confirm that all roles in postgreSQL are activated at login time?<br /><br />Secondly,
isthere a limit on the number of roles which can be assigned to a user (or more accurately a 'login role') in
postgreSQL?<br/><br />Many thanks,<br /><br />Andrew.<br /><br /><br /><hr />New Windows 7: Find the right PC for you.
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