ALTER DEFAULT PRIVILEGES — define default access privileges
ALTER DEFAULT PRIVILEGES
[ FOR { ROLE | USER } target_role [, ...] ]
[ IN SCHEMA schema_name [, ...] ]
abbreviated_grant_or_revoke
where abbreviated_grant_or_revoke is one of:
GRANT { { SELECT | INSERT | UPDATE | DELETE | TRUNCATE | REFERENCES | TRIGGER }
[, ...] | ALL [ PRIVILEGES ] }
ON TABLES
TO { [ GROUP ] role_name | PUBLIC } [, ...] [ WITH GRANT OPTION ]
GRANT { { USAGE | SELECT | UPDATE }
[, ...] | ALL [ PRIVILEGES ] }
ON SEQUENCES
TO { [ GROUP ] role_name | PUBLIC } [, ...] [ WITH GRANT OPTION ]
GRANT { EXECUTE | ALL [ PRIVILEGES ] }
ON { FUNCTIONS | ROUTINES }
TO { [ GROUP ] role_name | PUBLIC } [, ...] [ WITH GRANT OPTION ]
GRANT { USAGE | ALL [ PRIVILEGES ] }
ON TYPES
TO { [ GROUP ] role_name | PUBLIC } [, ...] [ WITH GRANT OPTION ]
GRANT { USAGE | CREATE | ALL [ PRIVILEGES ] }
ON SCHEMAS
TO { [ GROUP ] role_name | PUBLIC } [, ...] [ WITH GRANT OPTION ]
REVOKE [ GRANT OPTION FOR ]
{ { SELECT | INSERT | UPDATE | DELETE | TRUNCATE | REFERENCES | TRIGGER }
[, ...] | ALL [ PRIVILEGES ] }
ON TABLES
FROM { [ GROUP ] role_name | PUBLIC } [, ...]
[ CASCADE | RESTRICT ]
REVOKE [ GRANT OPTION FOR ]
{ { USAGE | SELECT | UPDATE }
[, ...] | ALL [ PRIVILEGES ] }
ON SEQUENCES
FROM { [ GROUP ] role_name | PUBLIC } [, ...]
[ CASCADE | RESTRICT ]
REVOKE [ GRANT OPTION FOR ]
{ EXECUTE | ALL [ PRIVILEGES ] }
ON { FUNCTIONS | ROUTINES }
FROM { [ GROUP ] role_name | PUBLIC } [, ...]
[ CASCADE | RESTRICT ]
REVOKE [ GRANT OPTION FOR ]
{ USAGE | ALL [ PRIVILEGES ] }
ON TYPES
FROM { [ GROUP ] role_name | PUBLIC } [, ...]
[ CASCADE | RESTRICT ]
REVOKE [ GRANT OPTION FOR ]
{ USAGE | CREATE | ALL [ PRIVILEGES ] }
ON SCHEMAS
FROM { [ GROUP ] role_name | PUBLIC } [, ...]
[ CASCADE | RESTRICT ]
ALTER DEFAULT PRIVILEGES allows you to set the privileges
that will be applied to objects created in the future. (It does not
affect privileges assigned to already-existing objects.) Currently,
only the privileges for schemas, tables (including views and foreign
tables), sequences, functions, and types (including domains) can be
altered. For this command, functions include aggregates and procedures.
The words FUNCTIONS and ROUTINES are
equivalent in this command. (ROUTINES is preferred
going forward as the standard term for functions and procedures taken
together. In earlier LightDB releases, only the
word FUNCTIONS was allowed. It is not possible to set
default privileges for functions and procedures separately.)
You can change default privileges only for objects that will be created by yourself or by roles that you are a member of. The privileges can be set globally (i.e., for all objects created in the current database), or just for objects created in specified schemas.
As explained in Section 5.7,
the default privileges for any object type normally grant all grantable
permissions to the object owner, and may grant some privileges to
PUBLIC as well. However, this behavior can be changed by
altering the global default privileges with
ALTER DEFAULT PRIVILEGES.
Default privileges that are specified per-schema are added to whatever
the global default privileges are for the particular object type.
This means you cannot revoke privileges per-schema if they are granted
globally (either by default, or according to a previous ALTER
DEFAULT PRIVILEGES command that did not specify a schema).
Per-schema REVOKE is only useful to reverse the
effects of a previous per-schema GRANT.
target_role
The name of an existing role of which the current role is a member.
If FOR ROLE is omitted, the current role is assumed.
schema_name
The name of an existing schema. If specified, the default privileges
are altered for objects later created in that schema.
If IN SCHEMA is omitted, the global default privileges
are altered.
IN SCHEMA is not allowed when setting privileges
for schemas, since schemas can't be nested.
role_name
The name of an existing role to grant or revoke privileges for.
This parameter, and all the other parameters in
abbreviated_grant_or_revoke,
act as described under
GRANT or
REVOKE,
except that one is setting permissions for a whole class of objects
rather than specific named objects.
Use ltsql's \ddp command
to obtain information about existing assignments of default privileges.
The meaning of the privilege display is the same as explained for
\dp in Section 5.7.
If you wish to drop a role for which the default privileges have been
altered, it is necessary to reverse the changes in its default privileges
or use DROP OWNED BY to get rid of the default privileges entry
for the role.
Grant SELECT privilege to everyone for all tables (and views) you
subsequently create in schema myschema, and allow
role webuser to INSERT into them too:
ALTER DEFAULT PRIVILEGES IN SCHEMA myschema GRANT SELECT ON TABLES TO PUBLIC; ALTER DEFAULT PRIVILEGES IN SCHEMA myschema GRANT INSERT ON TABLES TO webuser;
Undo the above, so that subsequently-created tables won't have any more permissions than normal:
ALTER DEFAULT PRIVILEGES IN SCHEMA myschema REVOKE SELECT ON TABLES FROM PUBLIC; ALTER DEFAULT PRIVILEGES IN SCHEMA myschema REVOKE INSERT ON TABLES FROM webuser;
Remove the public EXECUTE permission that is normally granted on functions,
for all functions subsequently created by role admin:
ALTER DEFAULT PRIVILEGES FOR ROLE admin REVOKE EXECUTE ON FUNCTIONS FROM PUBLIC;
Note however that you cannot accomplish that effect
with a command limited to a single schema. This command has no effect,
unless it is undoing a matching GRANT:
ALTER DEFAULT PRIVILEGES IN SCHEMA public REVOKE EXECUTE ON FUNCTIONS FROM PUBLIC;
That's because per-schema default privileges can only add privileges to the global setting, not remove privileges granted by it.
There is no ALTER DEFAULT PRIVILEGES statement in the SQL
standard.