backends

Name

backends

description

backends is a built-in system table of doris, which is stored under the information_schema database. You can view the BE node information through the backends system table.

The backends table schema is:

  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。

The information displayed by the backends system table is basically consistent with the information displayed by the show backends statement. However, the types of each field in the backends system table are more specific, and you can use the backends system table to perform operations such as filtering and joining.

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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