PostgreSQL Cookbook

PostgreSQL — еще одна система БД с открытым кодом, пригодная и для ПО, и для веба, и для больших объемов данных. Наполненная практическими примерами книга поможет быстро её освоить.

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«A group is a system-wide database object that can be assigned privileges and have users added to it as members. A group is a role that cannot be used to log in to any database. It is also possible to grant membership in a group to another group, thereby allowing the member role use of privileges assigned to the group it is a member of. Database groups are global across a database cluster installation».