ndbinfo config_values表

该config_values表提供有关节点配置参数值的当前状态的信息。表中的每一行对应于给定节点上参数的当前值。

config_params表的列

该表的config_param列和该config_params表的param_number列使用相同的参数标识符。通过将这些列上的两个表连接起来，可以获得有关所需节点配置参数的详细信息。此处显示的查询提供了集群中每个数据节点上所有参数的当前值，按节点ID和参数名称排序：

SELECT    v.node_id AS 'Node Id',
          p.param_name AS 'Parameter',
          v.config_value AS 'Value'
FROM      config_values v
JOIN      config_params p
ON        v.config_param=p.param_number
WHERE     p.param_name NOT LIKE '\_\_%'
ORDER BY  v.node_id, p.param_name;

在用于简单测试的小型示例集群上运行时，上一个查询的部分输出：

+---------	+------------------------------------------	+----------------	+
| Node Id	| Parameter	| Value	|
+---------	+------------------------------------------	+----------------	+
|       2	| Arbitration	| 1	|
|       2	| ArbitrationTimeout	| 7500	|
|       2	| BackupDataBufferSize	| 16777216	|
|       2	| BackupDataDir	| /home/jon/data	|
|       2	| BackupDiskWriteSpeedPct	| 50	|
|       2	| BackupLogBufferSize	| 16777216	|

...

|       3	| TotalSendBufferMemory	| 0	|
|       3	| TransactionBufferMemory	| 1048576	|
|       3	| TransactionDeadlockDetectionTimeout	| 1200	|
|       3	| TransactionInactiveTimeout	| 4294967039	|
|       3	| TwoPassInitialNodeRestartCopy	| 0	|
|       3	| UndoDataBuffer	| 16777216	|
|       3	| UndoIndexBuffer	| 2097152	|
+---------	+------------------------------------------	+----------------	+
248 rows in set (0.02 sec)

该WHERE子句过滤掉名称以双下划线（__）开头的参数；这些参数保留给NDB开发人员用于测试和其他内部使用，并不打算在生产NDB群集中使用。

您可以通过发出适当的查询来获得更具体，更详细的输出，或两者兼而有之。本实施例提供的所有类型的有关可用信息NodeId，NoOfReplicas，HostName，DataMemory，IndexMemory，和TotalSendBufferMemory参数作为目前对于集群中的所有数据节点设置：

SELECT  p.param_name AS Name,
        v.node_id AS Node,
        p.param_type AS Type,
        p.param_default AS 'Default',
        p.param_min AS Minimum,
        p.param_max AS Maximum,
        CASE p.param_mandatory WHEN 1 THEN 'Y' ELSE 'N' END AS 'Required',
        v.config_value AS Current
FROM    config_params p
JOIN    config_values v
ON      p.param_number = v.config_param
WHERE   p. param_name
  IN ('NodeId', 'NoOfReplicas', 'HostName',
      'DataMemory', 'IndexMemory', 'TotalSendBufferMemory')\G

在具有两个用于简单测试的数据节点的小型NDB群集上运行时，此查询的输出如下所示（NDB 8.0.18及更高版本）：

*************************** 1. row***************************
    Name: NodeId
    Node: 2
    Type: unsigned
 Default:
 Minimum: 1
 Maximum: 144
Required: Y
 Current: 2
*************************** 2. row***************************
    Name: HostName
    Node: 2
    Type: string
 Default: localhost
 Minimum:
 Maximum:
Required: N
 Current: 127.0.0.1
*************************** 3. row***************************
    Name: TotalSendBufferMemory
    Node: 2
    Type: unsigned
 Default: 0
 Minimum: 262144
 Maximum: 4294967039
Required: N
 Current: 0
*************************** 4. row***************************
    Name: NoOfReplicas
    Node: 2
    Type: unsigned
 Default: 2
 Minimum: 1
 Maximum: 4
Required: N
 Current: 2
*************************** 5. row***************************
    Name: DataMemory
    Node: 2
    Type: unsigned
 Default: 102760448
 Minimum: 1048576
 Maximum: 1099511627776
Required: N
 Current: 524288000
*************************** 6. row***************************
    Name: NodeId
    Node: 3
    Type: unsigned
 Default:
 Minimum: 1
 Maximum: 144
Required: Y
 Current: 3
*************************** 7. row***************************
    Name: HostName
    Node: 3
    Type: string
 Default: localhost
 Minimum:
 Maximum:
Required: N
 Current: 127.0.0.1
*************************** 8. row***************************
    Name: TotalSendBufferMemory
    Node: 3
    Type: unsigned
 Default: 0
 Minimum: 262144
 Maximum: 4294967039
Required: N
 Current: 0
*************************** 9. row***************************
    Name: NoOfReplicas
    Node: 3
    Type: unsigned
 Default: 2
 Minimum: 1
 Maximum: 4
Required: N
 Current: 2
*************************** 10. row***************************
    Name: DataMemory
    Node: 3
    Type: unsigned
 Default: 102760448
 Minimum: 1048576
 Maximum: 1099511627776
Required: N
 Current: 524288000
10 rows in set (0.01 sec)