帮助命令介绍

帮助命令介绍

在管理 AntDB 集群的过程中，如果对某个命令的格式或者功能有任何的不明白，可以通过 help 命令查看该命令的功能描述和命令格式。

在 adb 客户端只要执行 \h 命令即可查看当前 ADBMGR 支持的所有命令列表，如下所示：

antdb=# \h 
Available help: 
  ADBMGR PROMOTE              ALTER ITEM                  CLEAN GTMCOORD              DROP USER                   LIST PARAM                  RESET COORDINATOR           START ALL 
  ADD COORDINATOR             ALTER JOB                   CLEAN MONITOR               FAILOVER DATANODE           MONITOR AGENT               RESET DATANODE              START COORDINATOR 
  ADD DATANODE                ALTER USER                  CONFIG DATANODE             FAILOVER GTMCOORD           MONITOR ALL                 RESET GTMCOORD              START DATANODE 
  ADD GTMCOORD                APPEND ACTIVATE COORDINATOR CREATE USER                 FLUSH HOST                  MONITOR COORDINATOR         REVOKE                      START GTMCOORD 
  ADD HBA                     APPEND COORDINATOR          DEPLOY                      GRANT                       MONITOR DATANODE            REWIND DATANODE             STOP AGENT 
  ADD HOST                    APPEND COORDINATOR FOR      DROP COORDINATOR            INIT ALL                    MONITOR GTMCOORD            REWIND GTMCOORD             STOP ALL 
  ADD ITEM                    APPEND DATANODE             DROP DATANODE               LIST ACL                    MONITOR HA                  SET CLUSTER INIT            STOP COORDINATOR 
  ADD JOB                     APPEND GTMCOORD             DROP GTMCOORD               LIST HBA                    PROMOTE DATANODE            SET COORDINATOR             STOP DATANODE 
  ALTER COORDINATOR           CHECKOUT DN SLAVE STATUS    DROP HBA                    LIST HOST                   PROMOTE GTMCOORD            SET DATANODE                STOP GTMCOORD 
  ALTER DATANODE              CLEAN ALL                   DROP HOST                   LIST ITEM                   REMOVE COORDINATOR          SET GTMCOORD                SWITCHOVER DATANODE 
  ALTER GTMCOORD              CLEAN COORDINATOR           DROP ITEM                   LIST JOB                    REMOVE DATANODE             SHOW                        SWITCHOVER GTMCOORD 
  ALTER HOST                  CLEAN DATANODE              DROP JOB                    LIST NODE                   REMOVE GTMCOORD             START AGENT                  
antdb=#   

也可通过在 \h 后面添加具体的命令名称，查看指定命令的功能和格式。如下所示，\h start 展示 start 相关命令：

antdb=# \h start 
Command:     START AGENT 
Description: start the agent process on the ADB cluster 
Syntax: 
START AGENT { ALL | host_name [, ...] } [ PASSWORD passwd ] 
 
Command:     START ALL 
Description: start all the nodes on the ADB cluster 
Syntax: 
START ALL 
 
Command:     START COORDINATOR 
Description: start the coordinator node type on the ADB cluster 
Syntax: 
START COORDINATOR [ MASTER | SLAVE ] ALL 
START COORDINATOR { MASTER | SLAVE } node_name [, ...] 
 
Command:     START DATANODE 
Description: start the datanode node type on the ADB cluster 
Syntax: 
START DATANODE ALL 
START DATANODE { MASTER | SLAVE } { ALL | node_name [, ...] } 
 
Command:     START GTMCOORD 
Description: start the gtmcoord node type on the ADB cluster 
Syntax: 
START GTMCOORD ALL 
START GTMCOORD { MASTER | SLAVE } node_name 

下面章节的所有命令都可以通过上面的方式查看帮助信息。