Query the operator structure of an execution plan|V4.3.6| docs|Distributed Database

Query the operator structure of an execution plan

Last Updated：2025-09-08 08:15:43 Updated

Function Description

Queries the operator structure of an execution plan. The result set contains ordered operator information in a tree structure.

Call instructions

Interface constraints

The caller must have the read permission for the specified tenant.

Request path

GET /api/v2/cluters/{clusterId}/tenants/{tenantId}/plans/{uid}/explain

Request parameters

Parameter	Type	Required	Example Value	Description
clusterId	Integer	Yes	1	The ID of the cluster.
tenantId	Integer	Yes	1001	The ID of the tenant.
uid	String	Yes	AAAAAAAAAAEAAAAAAAKOvgAFs1_j8s3i	The UID of the plan.
startTime	Datetime	Yes	2020-02-16T05:32:16+08:00	The start time.
endTime	Datetime	Yes	2020-02-16T07:32:16+08:00	The end time.

Return results

Basic data structure

Parameter	Type	Description
data	Object	The request data.
├─ data	Array	The array of execution plan operators. The data structure of an execution plan operator is described in the following table.
├─ notEmpty	Boolean	Plan Explain.
├─ planOperationSummery	Array	The array of operation lists. The data structure of an operation list is described in the following table.
├─ rootOperations	Array	The array of operation operators. The data structure of an operation operator is described in the following table.
successful	Boolean	Indicates whether the request is successful.
timestamp	Datetime	The timestamp when the server finishes the request.
duration	Integer	The time taken by the server to process the request (in milliseconds).
status	Integer	The HTTP status code that conforms to the HTTP status specification.
traceId	String	The Trace ID of the request, which is used for troubleshooting.
server	String	The address of the application service that responds to the request.

Data structure of an execution plan operator

Parameter	Type	Description
ClusterName	String	The name of the cluster.
CollectTimeUs	Long	The time when the plan is collected (in microseconds).
Cost	Integer	The cost of the operator.
CreateTime	String	The creation time.
FirstLoadTimeUs	Long	The time when the plan is first loaded (in microseconds).
Id	Long	The ID of the operator.
ObClusterId	Long	The ID of the OceanBase cluster.
ObServerId	Long	The server ID of OceanBase.
ObTenantId	Long	The ID of the OceanBase tenant.
ObjectName	String	The name of the operation target.
Operator	String	The logical operator.
PlanId	Long	The ID of the execution plan.
PlanUnionHash	String	The unique identifier of the plan, which is calculated based on the operations and targets of the plan.
Property	String	The output and filtering of the operation.
Rows	Long	The estimated number of rows.

Data structure of an operation list

Parameter	Type	Description
operator	String	The logical operator.
objectName	String	The operation target.

Data structure of an operation operator

Parameter	Type	Description
operator	String	The name of the operator.
objectName	String	The operation target, which is usually the name of a table.
rows	Integer	The number of rows operated.
cost	Integer	The cost of the operation.
property	String	The output and filtering of the operation.
children	Array	The array of child operators.

Example

Request example

Query the operation structure of the physical execution plan with Uid AAAAAAAAAAEAAAAAAAAJ_AAFszE_cnfR in the cluster with Id 1 and tenant with Id 1001, and the plan time range is from 2020-11-03T19:00:00+08:00 to 2020-11-03T20:00:00+08:00.

GET /api/v2/ob/clusters/1/tenants/1001/plans/AAAAAAAAAAEAAAAAAAAJ_AAFszE_cnfR/explain?startTime=2020-11-03T19%3A00%3A00%2B08%3A00&endTime=2020-11-03T20%3A00%3A00%2B08%3A00

Response example

{
    "duration": 75,
    "server": "a83ad33525",
    "status": 200,
    "successful": true,
    "timestamp": "2020-11-11T11:12:13.216+08:00",
    "traceId": "dc7f223f5f7f4ef6",
    "data": {
        "rootOperations": [
            {
                "cost": 2024,
                "objectName": "NULL",
                "operator": "PHY_SCALAR_AGGREGATE",
                "property": "NULL",
                "rows": 1,
                "children": [
                    {
                        "cost": 2000,
                        "objectName": "__all_virtual_memory_info",
                        "operator": "PHY_TABLE_SCAN",
                        "property": "table_rows:100000, physical_range_rows:100, logical_range_rows:100, index_back_rows:0, output_rows:100, est_method:basic_stat",
                        "rows": 100
                    }
                ]
            }
        ]
    }
}