View cluster parameters

You can view cluster parameters from the sys tenant or a user tenant.

There are several ways to view cluster parameters:

• Use the SHOW statement to view cluster parameters.

  You can view all parameters of the cluster and their descriptions except for hidden parameters (named in the _xx_xx format). If the setting of a hidden parameter is changed to a non-default value, you can also use the SHOW statement to view the hidden parameter.

• Query the GV$OB_PARAMETERS view for cluster parameters.

  The GV$OB_PARAMETERS view displays all parameters of the cluster, including hidden parameters (named in the _xx_xx format), and their descriptions. This is different from executing the SHOW statement.

For more information about parameters, see Parameters and system variables.

Use the SHOW statement to view cluster parameters

You can use the SHOW statement to view the values of cluster parameters from the sys tenant or a user tenant. In the sys tenant, you can specify the TENANT keyword to view the parameters of the specified tenant.

1. Log on to the sys tenant or a user tenant.

   Note that you must specify the corresponding parameters in the following sample code based on your actual database configurations.

   obclient -h10.xx.xx.xx -P2883 -utest@mysql#obdemo -p***** -A
   

   For more information about how to connect to a database, see Connection methods (MySQL mode) or Connection methods (Oracle mode).

2. Execute the following statement to view cluster parameters:

   obclient [xxx]> SHOW PARAMETERS [SHOW_PARAM_OPTS] [TENANT = tenant_name];
   

   Take note of the following points:

   • You can specify [LIKE 'pattern' | WHERE expr] in [SHOW_PARAM_OPTS]. The column attributes that can be specified in WHERE expr are the same as those returned by SHOW PARAMETERS.

   • You can specify the TENANT keyword to view the parameters of the specified tenant.

   • Here is an example of viewing parameters in the sys tenant or a user tenant:

     obclient [(none)]> SHOW PARAMETERS LIKE '%syslog_level%';
     

     The query result is as follows:

     +-------+----------+----------------+----------+--------------+-----------+-------+------------------------------------------------------------------------------------------------------------------------------+----------+---------+---------+-------------------+---------------+-----------+
     | zone  | svr_type | svr_ip         | svr_port | name         | data_type | value | info                                                                                                                         | section  | scope   | source  | edit_level        | default_value | isdefault |
     +-------+----------+----------------+----------+--------------+-----------+-------+------------------------------------------------------------------------------------------------------------------------------+----------+---------+---------+-------------------+---------------+-----------+
     | zone1 | observer | 172.xx.xxx.xxx |     2882 | syslog_level | STRING    | WDIAG | specifies the current level of logging. There are DEBUG, TRACE, WDIAG, EDIAG, INFO, WARN, ERROR, seven different log levels. | OBSERVER | CLUSTER | DEFAULT | DYNAMIC_EFFECTIVE | WDIAG         |         1 |
     +-------+----------+----------------+----------+--------------+-----------+-------+------------------------------------------------------------------------------------------------------------------------------+----------+---------+---------+-------------------+---------------+-----------+
     1 row in set
     

   • Here is an example of viewing parameters of the specified tenant in the sys tenant:

     obclient [(none)]> SHOW PARAMETERS LIKE '%syslog_level%' TENANT = mysql001;
     

     The query result is as follows:

     +-------+----------+----------------+----------+--------------+-----------+-------+------------------------------------------------------------------------------------------------------------------------------+----------+---------+---------+-------------------+---------------+-----------+
     | zone  | svr_type | svr_ip         | svr_port | name         | data_type | value | info                                                                                                                         | section  | scope   | source  | edit_level        | default_value | isdefault |
     +-------+----------+----------------+----------+--------------+-----------+-------+------------------------------------------------------------------------------------------------------------------------------+----------+---------+---------+-------------------+---------------+-----------+
     | zone1 | observer | 172.xx.xxx.xxx |     2882 | syslog_level | STRING    | WDIAG | specifies the current level of logging. There are DEBUG, TRACE, WDIAG, EDIAG, INFO, WARN, ERROR, seven different log levels. | OBSERVER | CLUSTER | DEFAULT | DYNAMIC_EFFECTIVE | WDIAG         |         1 |
     +-------+----------+----------------+----------+--------------+-----------+-------+------------------------------------------------------------------------------------------------------------------------------+----------+---------+---------+-------------------+---------------+-----------+
     1 row in set
     

   The following table describes in the columns in the query result.

   Column name	Description
   zone	The zone where the parameter exists.
   svr_type	The server type.
   svr_ip	The IP address of the server.
   svr_port	The port number of the server.
   name	The name of the parameter.
   data_type	The data type of the parameter. Valid values: STRING, CAPACITY, and so on.
   value	The value of the parameter. Note You can modify the parameter value for a specified zone or server. Therefore, the value of the parameter may vary based on zones and servers.
   info	The description of the parameter.
   section	The category of the parameter. Valid values: SSTABLE: an SSTable-related parameter. OBSERVER: an OBServer-related parameter. ROOT_SERVICE: a RootService-related parameter. TENANT: a tenant-related parameter. TRANS: a transaction-related parameter. LOAD_BALANCE: a load balancing-related parameter. DAILY_MERGE: a major compaction-related parameter. CLOG: a clog-related parameter. LOCATION_CACHE: a location cache-related parameter. CACHE: a cache-related parameter. RPC: an RPC-related parameter. OBPROXY: an ODP-related parameter.
   scope	The application scope of the parameter. Valid values: TENANT: indicates that the parameter is a tenant-level parameter. CLUSTER: indicates that the parameter is a cluster-level parameter.
   source	The source of the current value. Valid values: TENANT CLUSTER CMDLINE OBADMIN FILE DEFAULT
   edit_level	The modification behavior of the parameter. Valid values: READONLY: indicates that you cannot modify the parameter. STATIC_EFFECTIVE: indicates that you can modify the parameter but the modification takes effect only after the OBServer node is restarted. DYNAMIC_EFFECTIVE: indicates that you can modify the parameter and the modification takes effect in real time.
   default_value	The default value of the parameter.
   isdefault	Indicates whether the current value is the default value. Valid values: 0: The current value is not the default value. 1: The current value is the default value.

Query the GV$OB_PARAMETERS view for cluster parameters

1. Log on to the sys tenant or a user tenant.

   Note that you must specify the corresponding options in the following sample code based on your actual database configurations.

   obclient -h10.xx.xx.xx -P2883 -utest@mysql#obdemo -p***** -A
   

   For more information about how to connect to a database, see Connection methods (MySQL mode) or Connection methods (Oracle mode).

2. Run the following command to access the oceanbase database:

   obclient > USE oceanbase;
   

   Note

   You need to perform this step only in a MySQL tenant. Skip this step in an Oracle tenant.

3. Execute the following statement to view cluster parameters:

   obclient> SELECT * FROM GV$OB_PARAMETERS WHERE NAME LIKE '%syslog_level%';
   

   The query result is as follows:

   +----------------+----------+-------+---------+-----------+--------------+-----------+-------+------------------------------------------------------------------------------------------------------------------------------+----------+-------------------+---------------+-----------+
   | SVR_IP         | SVR_PORT | ZONE  | SCOPE   | TENANT_ID | NAME         | DATA_TYPE | VALUE | INFO                                                                                                                         | SECTION  | EDIT_LEVEL        | DEFAULT_VALUE | ISDEFAULT |
   +----------------+----------+-------+---------+-----------+--------------+-----------+-------+------------------------------------------------------------------------------------------------------------------------------+----------+-------------------+---------------+-----------+
   | 172.xx.xxx.xxx |     2882 | zone1 | CLUSTER |      NULL | syslog_level | STRING    | WDIAG | specifies the current level of logging. There are DEBUG, TRACE, WDIAG, EDIAG, INFO, WARN, ERROR, seven different log levels. | OBSERVER | DYNAMIC_EFFECTIVE | WDIAG         | YES       |
   +----------------+----------+-------+---------+-----------+--------------+-----------+-------+------------------------------------------------------------------------------------------------------------------------------+----------+-------------------+---------------+-----------+
   1 row in set
   

For more information about the GV$OB_PARAMETERS view, see GV$OB_PARAMETERS (MySQL mode).

References

For more information about cluster parameters, see the following topics:

• Cluster parameters

• Modify cluster parameters

• Reset cluster parameters

• System variables of a tenant

For detailed information about each parameter, see Parameters and system variables.