backends

Name

SinceVersion 1.2

backends

description

backends 是doris内置的一张系统表，存放在information_schema数据库下。通过backends系统表可以查看当前doris集群中的 BE 节点信息。

backends 表结构为：

  1. MySQL [information_schema]> desc information_schema.backends;
  2. +-----------------------+-------------+------+-------+---------+-------+
  3. | Field                 | Type        | Null | Key   | Default | Extra |
  4. +-----------------------+-------------+------+-------+---------+-------+
  5. | BackendId             | BIGINT      | Yes  | false | NULL    |       |
  6. | Cluster               | VARCHAR(40) | Yes  | false | NULL    |       |
  7. | IP                    | VARCHAR(40) | Yes  | false | NULL    |       |
  8. | HeartbeatPort         | INT         | Yes  | false | NULL    |       |
  9. | BePort                | INT         | Yes  | false | NULL    |       |
  10. | HttpPort              | INT         | Yes  | false | NULL    |       |
  11. | BrpcPort              | INT         | Yes  | false | NULL    |       |
  12. | LastStartTime         | VARCHAR(40) | Yes  | false | NULL    |       |
  13. | LastHeartbeat         | VARCHAR(40) | Yes  | false | NULL    |       |
  14. | Alive                 | VARCHAR(40) | Yes  | false | NULL    |       |
  15. | SystemDecommissioned  | VARCHAR(40) | Yes  | false | NULL    |       |
  16. | ClusterDecommissioned | VARCHAR(40) | Yes  | false | NULL    |       |
  17. | TabletNum             | BIGINT      | Yes  | false | NULL    |       |
  18. | DataUsedCapacity      | BIGINT      | Yes  | false | NULL    |       |
  19. | AvailCapacity         | BIGINT      | Yes  | false | NULL    |       |
  20. | TotalCapacity         | BIGINT      | Yes  | false | NULL    |       |
  21. | UsedPct               | DOUBLE      | Yes  | false | NULL    |       |
  22. | MaxDiskUsedPct        | DOUBLE      | Yes  | false | NULL    |       |
  23. | RemoteUsedCapacity    | BIGINT      | Yes  | false | NULL    |       |
  24. | Tag                   | VARCHAR(40) | Yes  | false | NULL    |       |
  25. | ErrMsg                | VARCHAR(40) | Yes  | false | NULL    |       |
  26. | Version               | VARCHAR(40) | Yes  | false | NULL    |       |
  27. | Status                | VARCHAR(40) | Yes  | false | NULL    |       |
  28. +-----------------------+-------------+------+-------+---------+-------+

backends 系统表展示出来的信息基本与 show backends 语句展示出的信息一致。但是backends系统表的各个字段类型更加明确，且可以利用 backends 系统表去做过滤、join等操作。

Example

  1. MySQL [information_schema]> select * from  information_schema.backends;
  2. +-----------+-----------------+-----------+---------------+--------+----------+----------+---------------------+---------------------+-------+----------------------+-----------------------+-----------+------------------+---------------+---------------+--------------------+------------------+--------------------+--------------------------+--------+-----------------------------+-------------------------------------------------------------------------------------------------------------------------------+
  3. | BackendId | Cluster         | IP        | HeartbeatPort | BePort | HttpPort | BrpcPort | LastStartTime       | LastHeartbeat       | Alive | SystemDecommissioned | ClusterDecommissioned | TabletNum | DataUsedCapacity | AvailCapacity | TotalCapacity | UsedPct            | MaxDiskUsedPct   | RemoteUsedCapacity | Tag                      | ErrMsg | Version                     | Status                                                                                                                        |
  4. +-----------+-----------------+-----------+---------------+--------+----------+----------+---------------------+---------------------+-------+----------------------+-----------------------+-----------+------------------+---------------+---------------+--------------------+------------------+--------------------+--------------------------+--------+-----------------------------+-------------------------------------------------------------------------------------------------------------------------------+
  5. |     10757 | default_cluster | 127.0.0.1 |          9159 |   9169 |     8149 |     8169 | 2022-11-24 11:16:31 | 2022-11-24 12:02:57 | true  | false                | false                 |        14 |                0 |  941359747073 | 3170529116160 | 70.309064746482065 | 70.3090647465136 |                  0 | {"location" : "default"} |        | doris-0.0.0-trunk-cc9545359 | {"lastSuccessReportTabletsTime":"2022-11-24 12:02:06","lastStreamLoadTime":-1,"isQueryDisabled":false,"isLoadDisabled":false} |
  6. +-----------+-----------------+-----------+---------------+--------+----------+----------+---------------------+---------------------+-------+----------------------+-----------------------+-----------+------------------+---------------+---------------+--------------------+------------------+--------------------+--------------------------+--------+-----------------------------+-------------------------------------------------------------------------------------------------------------------------------+

KeyWords

  1. backends, information_schema

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