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GRANT(7)                         SQL Commands                         GRANT(7)



NAME
       GRANT - define access privileges


SYNOPSIS
       GRANT { { SELECT | INSERT | UPDATE | DELETE | TRUNCATE | REFERENCES | TRIGGER }
           [,...] | ALL [ PRIVILEGES ] }
           ON [ TABLE ] tablename [, ...]
           TO { [ GROUP ] rolename | PUBLIC } [, ...] [ WITH GRANT OPTION ]

       GRANT { { SELECT | INSERT | UPDATE | REFERENCES } ( column [, ...] )
           [,...] | ALL [ PRIVILEGES ] ( column [, ...] ) }
           ON [ TABLE ] tablename [, ...]
           TO { [ GROUP ] rolename | PUBLIC } [, ...] [ WITH GRANT OPTION ]

       GRANT { { USAGE | SELECT | UPDATE }
           [,...] | ALL [ PRIVILEGES ] }
           ON SEQUENCE sequencename [, ...]
           TO { [ GROUP ] rolename | PUBLIC } [, ...] [ WITH GRANT OPTION ]

       GRANT { { CREATE | CONNECT | TEMPORARY | TEMP } [,...] | ALL [ PRIVILEGES ] }
           ON DATABASE dbname [, ...]
           TO { [ GROUP ] rolename | PUBLIC } [, ...] [ WITH GRANT OPTION ]

       GRANT { USAGE | ALL [ PRIVILEGES ] }
           ON FOREIGN DATA WRAPPER fdwname [, ...]
           TO { [ GROUP ] rolename | PUBLIC } [, ...] [ WITH GRANT OPTION ]

       GRANT { USAGE | ALL [ PRIVILEGES ] }
           ON FOREIGN SERVER servername [, ...]
           TO { [ GROUP ] rolename | PUBLIC } [, ...] [ WITH GRANT OPTION ]

       GRANT { EXECUTE | ALL [ PRIVILEGES ] }
           ON FUNCTION funcname ( [ [ argmode ] [ argname ] argtype [, ...] ] ) [, ...]
           TO { [ GROUP ] rolename | PUBLIC } [, ...] [ WITH GRANT OPTION ]

       GRANT { USAGE | ALL [ PRIVILEGES ] }
           ON LANGUAGE langname [, ...]
           TO { [ GROUP ] rolename | PUBLIC } [, ...] [ WITH GRANT OPTION ]

       GRANT { { CREATE | USAGE } [,...] | ALL [ PRIVILEGES ] }
           ON SCHEMA schemaname [, ...]
           TO { [ GROUP ] rolename | PUBLIC } [, ...] [ WITH GRANT OPTION ]

       GRANT { CREATE | ALL [ PRIVILEGES ] }
           ON TABLESPACE tablespacename [, ...]
           TO { [ GROUP ] rolename | PUBLIC } [, ...] [ WITH GRANT OPTION ]

       GRANT role [, ...] TO rolename [, ...] [ WITH ADMIN OPTION ]


DESCRIPTION
       The GRANT command has two basic variants: one that grants privileges on a database object (table, column, view,
       sequence,  database,  foreign-data  wrapper,  foreign  server,  function,  procedural  language,   schema,   or
       tablespace),  and  one  that grants membership in a role. These variants are similar in many ways, but they are
       different enough to be described separately.

       As of PostgreSQL 8.1, the concepts of users and groups have been unified into a single kind of entity called  a
       role.   It is therefore no longer necessary to use the keyword GROUP to identify whether a grantee is a user or
       a group. GROUP is still allowed in the command, but it is a noise word.

   GRANT ON DATABASE OBJECTS
       This variant of the GRANT command gives specific privileges on a database object to one or  more  roles.  These
       privileges are added to those already granted, if any.

       The key word PUBLIC indicates that the privileges are to be granted to all roles, including those that might be
       created later. PUBLIC can be thought of as an implicitly defined group that always  includes  all  roles.   Any
       particular  role  will  have the sum of privileges granted directly to it, privileges granted to any role it is
       presently a member of, and privileges granted to PUBLIC.

       If WITH GRANT OPTION is specified, the recipient of the privilege can in turn grant it  to  others.  Without  a
       grant option, the recipient cannot do that. Grant options cannot be granted to PUBLIC.

       There is no need to grant privileges to the owner of an object (usually the user that created it), as the owner
       has all privileges by default. (The owner could, however, choose to revoke  some  of  his  own  privileges  for
       safety.)   The  right  to drop an object, or to alter its definition in any way is not described by a grantable
       privilege; it is inherent in the owner, and cannot be granted or revoked. The owner implicitly  has  all  grant
       options for the object, too.

       Depending  on the type of object, the initial default privileges might include granting some privileges to PUB-
       LIC.  The default is no public access for tables, columns, schemas, and tablespaces; CONNECT privilege and TEMP
       table  creation  privilege  for  databases; EXECUTE privilege for functions; and USAGE privilege for languages.
       The object owner can of course revoke these privileges. (For maximum security, issue the  REVOKE  in  the  same
       transaction that creates the object; then there is no window in which another user can use the object.)

       The possible privileges are:

       SELECT Allows SELECT [select(7)] from any column, or the specific columns listed, of the specified table, view,
              or sequence.  Also allows the use of COPY [copy(7)] TO.  This privilege  is  also  needed  to  reference
              existing  column values in UPDATE [update(7)] or DELETE [delete(7)].  For sequences, this privilege also
              allows the use of the currval function.

       INSERT Allows INSERT [insert(7)] of a new row into the specified table. If specific columns  are  listed,  only
              those  columns  may  be  assigned to in the INSERT command (other columns will therefore receive default
              values).  Also allows COPY [copy(7)] FROM.

       UPDATE Allows UPDATE [update(7)] of any column, or the specific columns listed, of the  specified  table.   (In
              practice,  any  nontrivial UPDATE command will require SELECT privilege as well, since it must reference
              table columns to determine which rows to update, and/or to compute new values for columns.)  SELECT  ...
              FOR  UPDATE  and SELECT ... FOR SHARE also require this privilege on at least one column, in addition to
              the SELECT privilege. For sequences, this privilege allows the use of the nextval and setval  functions.

       DELETE Allows  DELETE  [delete(7)] of a row from the specified table.  (In practice, any nontrivial DELETE com-
              mand will require SELECT privilege as well, since it must reference table  columns  to  determine  which
              rows to delete.)

       TRUNCATE
              Allows TRUNCATE [truncate(7)] on the specified table.

       REFERENCES
              To  create  a foreign key constraint, it is necessary to have this privilege on both the referencing and
              referenced columns. The privilege may be granted for all columns of a table, or just specific columns.

       TRIGGER
              Allows the creation of a trigger on the specified table. (See  the  CREATE  TRIGGER  [create_trigger(7)]
              statement.)

       CREATE For databases, allows new schemas to be created within the database.

              For schemas, allows new objects to be created within the schema.  To rename an existing object, you must
              own the object and have this privilege for the containing schema.

              For tablespaces, allows tables, indexes, and temporary files to be created within  the  tablespace,  and
              allows databases to be created that have the tablespace as their default tablespace. (Note that revoking
              this privilege will not alter the placement of existing objects.)

       CONNECT
              Allows the user to connect to the specified database. This privilege is checked  at  connection  startup
              (in addition to checking any restrictions imposed by pg_hba.conf).

       TEMPORARY

       TEMP   Allows temporary tables to be created while using the specified database.

       EXECUTE
              Allows the use of the specified function and the use of any operators that are implemented on top of the
              function. This is the only type of privilege that is applicable to functions.  (This  syntax  works  for
              aggregate functions, as well.)

       USAGE  For procedural languages, allows the use of the specified language for the creation of functions in that
              language. This is the only type of privilege that is applicable to procedural languages.

              For schemas, allows access to objects contained in the specified schema (assuming that the objects'  own
              privilege  requirements are also met). Essentially this allows the grantee to ''look up'' objects within
              the schema. Without this permission, it is still possible to see the object names, e.g. by querying  the
              system  tables.  Also, after revoking this permission, existing backends might have statements that have
              previously performed this lookup, so this is not a completely secure way to prevent object access.

              For sequences, this privilege allows the use of the currval and nextval functions.

              For foreign-data wrappers, this privilege enables the grantee to create new servers using that  foreign-
              data wrapper.

              For  servers, this privilege enables the grantee to create, alter, and drop his own user's user mappings
              associated with that server. Also, it enables the grantee to query the options of the server and associ-
              ated user mappings.

       ALL PRIVILEGES
              Grant  all  of  the  available  privileges  at once.  The PRIVILEGES key word is optional in PostgreSQL,
              though it is required by strict SQL.

       The privileges required by other commands are listed on the reference page of the respective command.

   GRANT ON ROLES
       This variant of the GRANT command grants membership in a role to one or more other roles. Membership in a  role
       is significant because it conveys the privileges granted to a role to each of its members.

       If  WITH  ADMIN  OPTION is specified, the member can in turn grant membership in the role to others, and revoke
       membership in the role as well. Without the admin option, ordinary users cannot do that. A role is not  consid-
       ered  to hold WITH ADMIN OPTION on itself, but it may grant or revoke membership in itself from a database ses-
       sion where the session user matches the role. Database superusers can grant or revoke membership in any role to
       anyone. Roles having CREATEROLE privilege can grant or revoke membership in any role that is not a superuser.

       Unlike  the case with privileges, membership in a role cannot be granted to PUBLIC. Note also that this form of
       the command does not allow the noise word GROUP.

NOTES
       The REVOKE [revoke(7)] command is used to revoke access privileges.

       A user may perform SELECT, INSERT, etc. on a column if he holds that privilege for either the  specific  column
       or  its  whole table. Granting the privilege at the table level and then revoking it for one column will not do
       what you might wish: the table-level grant is unaffected by a column-level operation.

       When a non-owner of an object attempts to GRANT privileges on the object, the command will fail outright if the
       user  has no privileges whatsoever on the object. As long as some privilege is available, the command will pro-
       ceed, but it will grant only those privileges for which the user has grant options. The  GRANT  ALL  PRIVILEGES
       forms  will issue a warning message if no grant options are held, while the other forms will issue a warning if
       grant options for any of the privileges specifically named in the command are not held.   (In  principle  these
       statements  apply  to  the  object  owner  as  well, but since the owner is always treated as holding all grant
       options, the cases can never occur.)

       It should be noted that database superusers can access all objects regardless  of  object  privilege  settings.
       This is comparable to the rights of root in a Unix system.  As with root, it's unwise to operate as a superuser
       except when absolutely necessary.

       If a superuser chooses to issue a GRANT or REVOKE command, the command is performed as though it were issued by
       the owner of the affected object. In particular, privileges granted via such a command will appear to have been
       granted by the object owner.  (For role membership, the membership appears to have been granted by the contain-
       ing role itself.)

       GRANT  and  REVOKE  can also be done by a role that is not the owner of the affected object, but is a member of
       the role that owns the object, or is a member of a role that holds privileges WITH GRANT OPTION on the  object.
       In  this  case the privileges will be recorded as having been granted by the role that actually owns the object
       or holds the privileges WITH GRANT OPTION. For example, if table t1 is owned by role g1, of which role u1 is  a
       member,  then  u1  can  grant  privileges  on  t1  to u2, but those privileges will appear to have been granted
       directly by g1. Any other member of role g1 could revoke them later.

       If the role executing GRANT holds the required privileges indirectly via more than one role membership path, it
       is  unspecified which containing role will be recorded as having done the grant. In such cases it is best prac-
       tice to use SET ROLE to become the specific role you want to do the GRANT as.

       Granting permission on a table does not automatically extend permissions to any sequences used  by  the  table,
       including sequences tied to SERIAL columns. Permissions on sequences must be set separately.

       Use psql(1)'s \dp command to obtain information about existing privileges for tables and columns. For example:

       => \dp mytable
                                     Access privileges
        Schema |  Name   | Type  |   Access privileges   | Column access privileges
       --------+---------+-------+-----------------------+--------------------------
        public | mytable | table | miriam=arwdDxt/miriam | col1:
                                 : =r/miriam             :   miriam_rw=rw/miriam
                                 : admin=arw/miriam
       (1 row)

       The entries shown by \dp are interpreted thus:

             rolename=xxxx -- privileges granted to a role
                     =xxxx -- privileges granted to PUBLIC

                         r -- SELECT ("read")
                         w -- UPDATE ("write")
                         a -- INSERT ("append")
                         d -- DELETE
                         D -- TRUNCATE
                         x -- REFERENCES
                         t -- TRIGGER
                         X -- EXECUTE
                         U -- USAGE
                         C -- CREATE
                         c -- CONNECT
                         T -- TEMPORARY
                   arwdDxt -- ALL PRIVILEGES (for tables, varies for other objects)
                         * -- grant option for preceding privilege

                     /yyyy -- role that granted this privilege

       The above example display would be seen by user miriam after creating table mytable and doing:

       GRANT SELECT ON mytable TO PUBLIC;
       GRANT SELECT, UPDATE, INSERT ON mytable TO admin;
       GRANT SELECT (col1), UPDATE (col1) ON mytable TO miriam_rw;


       For non-table objects there are other \d commands that can display their privileges.

       If  the  ''Access  privileges''  column is empty for a given object, it means the object has default privileges
       (that is, its privileges column is null). Default privileges always include all privileges for the  owner,  and
       can  include  some  privileges  for PUBLIC depending on the object type, as explained above. The first GRANT or
       REVOKE on an object will instantiate the default privileges (producing, for  example,  {miriam=arwdDxt/miriam})
       and  then  modify  them  per  the specified request. Entries are shown in ''Column access privileges'' only for
       columns with nondefault privileges.

       Notice that the owner's implicit grant options are not marked in the access privileges display. A * will appear
       only when grant options have been explicitly granted to someone.

EXAMPLES
       Grant insert privilege to all users on table films:

       GRANT INSERT ON films TO PUBLIC;


       Grant all available privileges to user manuel on view kinds:

       GRANT ALL PRIVILEGES ON kinds TO manuel;

       Note  that  while  the above will indeed grant all privileges if executed by a superuser or the owner of kinds,
       when executed by someone else it will only grant those  permissions  for  which  the  someone  else  has  grant
       options.

       Grant membership in role admins to user joe:

       GRANT admins TO joe;


COMPATIBILITY
       According to the SQL standard, the PRIVILEGES key word in ALL PRIVILEGES is required. The SQL standard does not
       support setting the privileges on more than one object per command.

       PostgreSQL allows an object owner to revoke his own ordinary privileges: for example, a table  owner  can  make
       the table read-only to himself by revoking his own INSERT, UPDATE, DELETE, and TRUNCATE privileges. This is not
       possible according to the SQL standard. The reason is that PostgreSQL treats the owner's privileges  as  having
       been granted by the owner to himself; therefore he can revoke them too. In the SQL standard, the owner's privi-
       leges are granted by an assumed entity ''_SYSTEM''. Not  being  ''_SYSTEM'',  the  owner  cannot  revoke  these
       rights.

       The SQL standard provides for a USAGE privilege on other kinds of objects: character sets, collations, transla-
       tions, domains.

       Privileges on databases, tablespaces, schemas, and languages are PostgreSQL extensions.

SEE ALSO
       REVOKE [revoke(7)]



SQL - Language Statements         2014-02-17                          GRANT(7)