backends

Name

SinceVersion dev

backends

description

表函数，生成backends临时表，可以查看当前doris集群中的 BE 节点信息。

该函数用于from子句中。

syntax

backends()

backends()表结构：

1. mysql> desc function backends();
2. +-------------------------+---------+------+-------+---------+-------+
3. | Field                   | Type    | Null | Key   | Default | Extra |
4. +-------------------------+---------+------+-------+---------+-------+
5. | BackendId               | BIGINT  | No   | false | NULL    | NONE  |
6. | Host                    | TEXT    | No   | false | NULL    | NONE  |
7. | HeartbeatPort           | INT     | No   | false | NULL    | NONE  |
8. | BePort                  | INT     | No   | false | NULL    | NONE  |
9. | HttpPort                | INT     | No   | false | NULL    | NONE  |
10. | BrpcPort                | INT     | No   | false | NULL    | NONE  |
11. | LastStartTime           | TEXT    | No   | false | NULL    | NONE  |
12. | LastHeartbeat           | TEXT    | No   | false | NULL    | NONE  |
13. | Alive                   | BOOLEAN | No   | false | NULL    | NONE  |
14. | SystemDecommissioned    | BOOLEAN | No   | false | NULL    | NONE  |
15. | TabletNum               | BIGINT  | No   | false | NULL    | NONE  |
16. | DataUsedCapacity        | BIGINT  | No   | false | NULL    | NONE  |
17. | AvailCapacity           | BIGINT  | No   | false | NULL    | NONE  |
18. | TotalCapacity           | BIGINT  | No   | false | NULL    | NONE  |
19. | UsedPct                 | DOUBLE  | No   | false | NULL    | NONE  |
20. | MaxDiskUsedPct          | DOUBLE  | No   | false | NULL    | NONE  |
21. | RemoteUsedCapacity      | BIGINT  | No   | false | NULL    | NONE  |
22. | Tag                     | TEXT    | No   | false | NULL    | NONE  |
23. | ErrMsg                  | TEXT    | No   | false | NULL    | NONE  |
24. | Version                 | TEXT    | No   | false | NULL    | NONE  |
25. | Status                  | TEXT    | No   | false | NULL    | NONE  |
26. | HeartbeatFailureCounter | INT     | No   | false | NULL    | NONE  |
27. | NodeRole                | TEXT    | No   | false | NULL    | NONE  |
28. +-------------------------+---------+------+-------+---------+-------+
29. 23 rows in set (0.002 sec)

backends() tvf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() tvf的各个字段类型更加明确，且可以利用tvf生成的表去做过滤、join等操作。

对 backends() tvf信息展示进行了鉴权，与 show backends 行为保持一致，要求用户具有 ADMIN/OPERATOR 权限。

example

1. mysql> select * from backends()\G
2. *************************** 1. row ***************************
3. BackendId: 10002
4. Host: 10.xx.xx.90
5. HeartbeatPort: 9053
6. BePort: 9063
7. HttpPort: 8043
8. BrpcPort: 8069
9. LastStartTime: 2023-06-15 16:51:02
10. LastHeartbeat: 2023-06-15 17:09:58
11. Alive: 1
12. SystemDecommissioned: 0
13. TabletNum: 21
14. DataUsedCapacity: 0
15. AvailCapacity: 5187141550081
16. TotalCapacity: 7750977622016
17. UsedPct: 33.077583202570978
18. MaxDiskUsedPct: 33.077583202583881
19. RemoteUsedCapacity: 0
20. Tag: {"location" : "default"}
21. ErrMsg:
22. Version: doris-0.0.0-trunk-4b18cde0c7
23. Status: {"lastSuccessReportTabletsTime":"2023-06-15 17:09:02","lastStreamLoadTime":-1,"isQueryDisabled":false,"isLoadDisabled":false}
24. HeartbeatFailureCounter: 0
25. NodeRole: mix
26. 1 row in set (0.038 sec)

keywords

1. backends