Modify a tenant

This topic describes how to modify the attributes of a tenant.

Limitations

You can modify the attributes of a tenant only from the sys tenant.

Procedure

After a tenant is created, you can modify information about the tenant by using an SQL statement, including the number of replicas, zone list, primary zone, and system variables of the tenant.

1. Log on to the sys tenant as the root user.

2. Execute the following statement to modify tenant attributes.

   Sample statement:

   ALTER TENANT {tenant_name | ALL}
       [SET] [tenant_option_list] [opt_global_sys_vars_set]
   
   tenant_option_list:
       tenant_option [, tenant_option ...]
   
   tenant_option:
               COMMENT [=]'string'
               |PRIMARY_ZONE [=] zone
               |RESOURCE_POOL_LIST [=](poolname [, poolname...])
               |DEFAULT TABLEGROUP [=] {NULL | tablegroupname}
         |LOCALITY [=] 'locality description';
   
   opt_global_sys_vars_set:
         VARIABLES system_var_name = expr [,system_var_name = expr] ...
   

   Notes:

   • ALL indicates to modify all tenants.

   • PRIMARY_ZONE specifies the primary zone of the tenant.

   • RESOURCE_POOL_LIST specifies the list of resource pools. You can add or delete only one resource pool at a time.

     You cannot directly replace the resource pool of the tenant. Assume that the resource pool used by the tenant is pool1. The system returns an error if you execute the following statement to replace the resource pool with pool2:

     obclient> ALTER TENANT tenant1 resource_pool_list=('pool2');
     ERROR 1210 (HY000): Incorrect arguments to resource pool list
     

   • DEFAULT TABLEGROUP specifies the default table group of the tenant. If this parameter is set to NULL, the default table group of the database is disabled.

   • LOCALITY specifies the distribution of replicas across zones. For example, F@z1,F@z2,F@z3,R@z4 indicates that z1, z2, and z3 are full-featured replicas, and z4 is a read-only replica.

   Examples:

   • Change the primary zone of tenant1 to zone2.

     obclient> ALTER TENANT tenant1 primary_zone='zone2';
     

   • Modify the locality of tenant1 to increase the number of replicas.

     F indicates a full-featured replica, and B_4 is the name of the zone to be created.

     obclient> ALTER TENANT tenant1 locality="F@B_1,F@B_2,F@B_3,F@B_4"
     

More information

For more information about the ALTER TENANT statement, see ALTER TENANT.