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Permissions: GRANT, DENY, REVOKE

  • Artikkeli

Applies to: Azure Synapse Analytics Analytics Platform System (PDW) SQL analytics endpoint in Microsoft Fabric Warehouse in Microsoft Fabric

Use GRANT and DENY statements to grant or deny a permission (such as UPDATE) on a securable (such as a database, table, view, etc.) to a security principal (a login, a database user, or a database role). Use REVOKE to remove the grant or deny of a permission.

Server level permissions are applied to logins. Database level permissions are applied to database users and database roles.

To see what permissions have been granted and denied, query the sys.server_permissions and sys.database_permissions views. Permissions that are not explicitly granted or denied to a security principal can be inherited by having membership in a role that has permissions. The permissions of the fixed database roles cannot be changed and do not appear in the sys.server_permissions and sys.database_permissions views.

  • GRANT explicitly grants one or more permissions.

  • DENY explicitly denies the principal from having one or more permissions.

  • REVOKE removes existing GRANT or DENY permissions.

Transact-SQL syntax conventions

Syntax

-- Azure Synapse Analytics and Parallel Data Warehouse and Microsoft Fabric
GRANT   
    <permission> [ ,...n ]  
    [ ON [ <class_type> :: ] securable ]   
    TO principal [ ,...n ]  
    [ WITH GRANT OPTION ]  
[;]  
  
DENY   
    <permission> [ ,...n ]  
    [ ON [ <class_type> :: ] securable ]   
    TO principal [ ,...n ]  
    [ CASCADE ]  
[;]  
  
REVOKE   
    <permission> [ ,...n ]  
    [ ON [ <class_type> :: ] securable ]   
    [ FROM | TO ] principal [ ,...n ]  
    [ CASCADE ]  
[;]  
  
<permission> ::=  
{ see the tables below }  
  
<class_type> ::=  
{  
      LOGIN  
    | DATABASE  
    | OBJECT  
    | ROLE  
    | SCHEMA  
    | USER  
}

Arguments

<permission>[ ,...n ]
One or more permissions to grant, deny, or revoke.

ON [ <class_type> :: ] securable The ON clause describes the securable parameter on which to grant, deny, or revoke permissions.

<class_type> The class type of the securable. This can be LOGIN, DATABASE, OBJECT, SCHEMA, ROLE, or USER. Permissions can also be granted to the SERVERclass_type, but SERVER is not specified for those permissions. DATABASE is not specified when the permission includes the word DATABASE (for example ALTER ANY DATABASE). When no class_type is specified and the permission type is not restricted to the server or database class, the class is assumed to be OBJECT.

securable
The name of the login, database, table, view, schema, procedure, role, or user on which to grant, deny, or revoke permissions. The object name can be specified with the three-part naming rules that are described in Transact-SQL syntax conventions.

TO principal [ ,...n ]
One or more principals being granted, denied, or revoked permissions. Principal is the name of a login, database user, or database role.

FROM principal [ ,...n ]
One or more principals to revoke permissions from. Principal is the name of a login, database user, or database role. FROM can only be used with a REVOKE statement. TO can be used with GRANT, DENY, or REVOKE.

WITH GRANT OPTION
Indicates that the grantee will also be given the ability to grant the specified permission to other principals.

CASCADE
Indicates that the permission is denied or revoked to the specified principal and to all other principals to which the principal granted the permission. Required when the principal has the permission with GRANT OPTION.

GRANT OPTION FOR
Indicates that the ability to grant the specified permission will be revoked. This is required when you are using the CASCADE argument.

Important

If the principal has the specified permission without the GRANT option, the permission itself will be revoked.

Permissions

To grant a permission, the grantor must have either the permission itself with the WITH GRANT OPTION, or must have a higher permission that implies the permission being granted. Object owners can grant permissions on the objects they own. Principals with CONTROL permission on a securable can grant permission on that securable. Members of the db_owner and db_securityadmin fixed database roles can grant any permission in the database.

General Remarks

Denying or revoking permissions to a principal will not affect requests that have passed authorization and are currently running. To restrict access immediately, you must cancel active requests or kill current sessions.

Note

Most fixed server roles are not available in this release. Use user-defined database roles instead. Logins cannot be added to the sysadmin fixed server role. Granting the CONTROL SERVER permission approximates membership in the sysadmin fixed server role.

Some statements require multiple permissions. For example, to create a table requires the CREATE TABLE permissions in the database, and the ALTER SCHEMA permission for the table that will contain the table.

Analytics Platform System (PDW) sometimes executes stored procedures to distribute user actions to the compute nodes. Therefore, the execute permission for an entire database cannot be denied. (For example DENY EXECUTE ON DATABASE::<name> TO <user>; will fail.) As a work around, deny the execute permission to user-schemas or specific objects (procedures).

In Microsoft Fabric, currently the CREATE USER cannot be explicitly executed. When GRANT or DENY is executed, the user will be created automatically.

In Microsoft Fabric, server-level permissions are not manageable.

Implicit and Explicit Permissions

An explicit permission is a GRANT or DENY permission given to a principal by a GRANT or DENY statement.

An implicit permission is a GRANT or DENY permission that a principal (login, user, or database role) has inherited from another database role.

An implicit permission can also be inherited from a covering or parent permission. For example, UPDATE permission on a table can be inherited by having UPDATE permission on the schema that contains the table, or CONTROL permission on the table.

Ownership Chaining

When multiple database objects access each other sequentially, the sequence is known as a chain. Although such chains do not independently exist, when SQL Server traverses the links in a chain, SQL Server evaluates permissions on the constituent objects differently than it would if it were accessing the objects separately. Ownership chaining has important implications for managing security. For more information about ownership chains, see Ownership Chains and Tutorial: Ownership Chains and Context Switching.

Permission List

Server Level Permissions

Server level permissions can be granted, denied, and revoked from logins.

Permissions that apply to servers

  • CONTROL SERVER

  • ADMINISTER BULK OPERATIONS

  • ALTER ANY CONNECTION

  • ALTER ANY DATABASE

  • CREATE ANY DATABASE

  • ALTER ANY EXTERNAL DATA SOURCE

  • ALTER ANY EXTERNAL FILE FORMAT

  • ALTER ANY LOGIN

  • ALTER SERVER STATE

  • CONNECT SQL

  • VIEW ANY DEFINITION

  • VIEW ANY DATABASE

  • VIEW SERVER STATE

Permissions that apply to logins

  • CONTROL ON LOGIN

  • ALTER ON LOGIN

  • IMPERSONATE ON LOGIN

  • VIEW DEFINITION

Database Level Permissions

Database level permissions can be granted, denied, and revoked from database users and user-defined database roles.

Permissions that apply to all database classes

  • CONTROL

  • ALTER

  • VIEW DEFINITION

Permissions that apply to all database classes except users

  • TAKE OWNERSHIP

Permissions that apply only to databases

  • ALTER ANY DATABASE

  • ALTER ON DATABASE

  • ALTER ANY DATASPACE

  • ALTER ANY ROLE

  • ALTER ANY SCHEMA

  • ALTER ANY USER

  • BACKUP DATABASE

  • CONNECT ON DATABASE

  • CREATE PROCEDURE

  • CREATE ROLE

  • CREATE SCHEMA

  • CREATE TABLE

  • CREATE VIEW

  • SHOWPLAN

Permissions that apply only to users

  • IMPERSONATE

Permissions that apply to databases, schemas, and objects

  • ALTER

  • DELETE

  • EXECUTE

  • INSERT

  • SELECT

  • UPDATE

  • REFERENCES

For a definition of each type of permission, see Permissions (Database Engine).

Chart of Permissions

All permissions are graphically represented on this poster. This is the easiest way to see nested hierarchy of permissions. For example the ALTER ON LOGIN permission can be granted by itself, but it is also included if a login is granted the CONTROL permission on that login, or if a login is granted the ALTER ANY LOGIN permission.

APS security permissions poster

Default Permissions

The following list describes the default permissions:

  • When a login is created by using the CREATE LOGIN statement the new login receives the CONNECT SQL permission.

  • All logins are members of the public server role and cannot be removed from public.

  • When a database user is created by using the CREATE USER permission, the database user receives the CONNECT permission in the database.

  • All principals, including the public role, have no explicit or implicit permissions by default.

  • When a login or user becomes the owner of a database or object, the login or user always has all permissions on the database or object. The ownership permissions cannot be changed and are not visible as explicit permissions. The GRANT, DENY, and REVOKE statements have no effect on owners.

  • The sa login has all permissions on the appliance. Similar to ownership permissions, the sa permissions cannot be changed and are not visible as explicit permissions. The GRANT, DENY, and REVOKE statements have no effect on sa login. The sa login cannot be renamed.

  • The USE statement does not require permissions. All principals can run the USE statement on any database.

Examples: Azure Synapse Analytics and Analytics Platform System (PDW)

A. Granting a server level permission to a login

The following two statements grant a server level permission to a login.

GRANT CONTROL SERVER TO [Ted];  

GRANT ALTER ANY DATABASE TO Mary;

B. Granting a server level permission to a login

The following example grants a server level permission on a login to a server principal (another login).

GRANT  VIEW DEFINITION ON LOGIN::Ted TO Mary;

C. Granting a database level permission to a user

The following example grants a database level permission on a user to a database principal (another user).

GRANT VIEW DEFINITION ON USER::[Ted] TO Mary;

D. Granting, denying, and revoking a schema permission

The following GRANT statement grants Yuen the ability to select data from any table or view in the dbo schema.

GRANT SELECT ON SCHEMA::dbo TO [Yuen];

The following DENY statement prevents Yuen from selecting data from any table or view in the dbo schema. Yuen cannot read the data even if he has permission in some other way, such as through a role membership.

DENY SELECT ON SCHEMA::dbo TO [Yuen];

The following REVOKE statement removes the DENY permission. Now Yuen's explicit permissions are neutral. Yuen might be able to select data from any table through some other implicit permission such as a role membership.

REVOKE SELECT ON SCHEMA::dbo TO [Yuen];

E. Demonstrating the optional OBJECT:: clause

Because OBJECT is the default class for a permission statement, the following two statements are the same. The OBJECT:: clause is optional.

GRANT UPDATE ON OBJECT::dbo.StatusTable TO [Ted];  

GRANT UPDATE ON dbo.StatusTable TO [Ted];