Updated on 2026-07-20 GMT+08:00

Querying Lock Wait Sessions

Function

This API is used to query lock wait sessions by node ID and session ID. Before calling this API:

Calling Method

For details, see Calling APIs.

Authorization Information

Each account has all the permissions required to call all APIs, but IAM users must be assigned the required permissions.

  • If you are using role/policy-based authorization, see Permissions and Supported Actions for details on the required permissions.
  • If you are using identity policy-based authorization, the following identity policy-based permissions are required.

    Action

    Access Level

    Resource Type (*: required)

    Condition Key

    Alias

    Dependency

    gaussdbformysql:instance:listProcesses

    List

    instance *

    • g:EnterpriseProjectId

    • g:ResourceTag/<tag-key>

    gaussdb:instance:listProcesses

    -

URI

GET /v3/{project_id}/instances/{instance_id}/nodes/{node_id}/process/lock-wait

Table 1 URI parameters

Parameter

Mandatory

Type

Description

project_id

Yes

String

Definition

Project ID of a tenant in a region.

To obtain this value, see Obtaining a Project ID.

Constraints

N/A

Range

The value contains 32 characters. Only letters and digits are allowed.

Default Value

N/A

instance_id

Yes

String

Definition

Instance ID, which uniquely identifies an instance.

To obtain this value, see Querying DB Instances.

Constraints

N/A

Range

The value contains 36 characters with a suffix of in07. Only letters and digits are allowed.

Default Value

N/A

node_id

Yes

String

Definition

Node ID.

To obtain this value, see Querying Details of a DB Instance.

Constraints

N/A

Range

The value contains 36 characters. Only letters and digits are allowed.

Default Value

N/A

Table 2 Query parameters

Parameter

Mandatory

Type

Description

pid

Yes

Long

Definition

Process ID of the session.

To obtain this value, see Querying User Session Threads on a Node.

Constraints

The value cannot be left blank.

Range

The value must be a positive integer.

Default Value

N/A

Request Parameters

Table 3 Request header parameters

Parameter

Mandatory

Type

Description

X-Auth-Token

Yes

String

Definition

User token. To obtain this value, call the IAM API for obtaining a user token.

The value of X-Subject-Token in the response header is the token value.

Constraints

N/A

Range

N/A

Default Value

N/A

X-Language

No

String

Definition

Request language type.

Constraints

N/A

Range

  • en-us: English

  • zh-cn: Chinese

Default Value

en-us

Response Parameters

Status code: 200

Table 4 Response body parameter

Parameter

Type

Description

abnormal_root_cause

AbnormalRootCause object

Definition

Root cause information, including root cause analysis for lock waits or long-running transactions.

Table 5 AbnormalRootCause

Parameter

Type

Description

abnormal_type

String

Definition

Exception type.

Range

LOCK_WAIT: lock wait

lock_root_cause

LockRootCause object

Definition

Lock root cause information.

Table 6 LockRootCause

Parameter

Type

Description

locked_pid

Long

Definition

ID of the locked session.

Range

N/A

locked_sql

String

Definition

SQL statement being executed by the locked session.

Range

N/A

wait_seconds

Long

Definition

Wait duration, in seconds.

Range

N/A

lock_db

String

Definition

Database where the lock is located.

Range

N/A

lock_table

String

Definition

Table where the lock is located.

Range

N/A

lock_index

String

Definition

Index where the lock is located.

Range

N/A

lock_mode

String

Definition

Lock mode.

Range

  • IX: table-level exclusive lock

  • X,REC_NOT_GAP: exclusive record lock

  • X,GAP: gap lock

  • X: row-level exclusive lock

lock_data

String

Definition

Identifier of the locked data row.

Range

N/A

blocker_pid

Integer

Definition

Blocking session ID.

Range

N/A

blocker_state

String

Definition

Blocking transaction status.

Range

  • RUNNING

  • LOCK WAIT

  • ROLLING BACK

  • COMMITTING

blocker_age

Long

Definition

Blocking transaction duration, in seconds.

Range

N/A

blocker_rows_locked

Long

Definition

Number of rows locked by the blocking session.

Range

N/A

blocker_rows_modified

Long

Definition

Number of rows modified by the blocking session.

Range

N/A

blocker_current_sql

Array of strings

Definition

List of SQL statements being executed by the blocking session.

blocker_host

String

Definition

Blocking host.

Range

N/A

blocker_command

String

Definition

Blocking command.

Range

N/A

blocker_thread_id

Long

Definition

Blocking thread ID.

Range

N/A

Status code: 400

Table 7 Response body parameters

Parameter

Type

Description

error_code

String

Error code.

error_msg

String

Error message.

Example Request

Querying lock wait sessions

GET https://{endpoint}/v3/4879de6859e345c780f1a22d8bc6f229/instances/889e005a27254666813a78dba117c0b2in07/nodes/889e005a27254666813a78dba117c0b2no01/process/lock-wait?pid=483563

Example Response

Status code: 200

Success.

{
  "abnormal_root_cause" : {
    "abnormal_type" : "LOCK_WAIT",
    "lock_root_cause" : {
      "locked_pid" : 483563,
      "locked_sql" : "UPDATE t_lock_test SET val = 'leaf' WHERE id = 2",
      "wait_seconds" : 20,
      "lock_db" : "test",
      "lock_table" : "table1",
      "lock_index" : "30",
      "lock_data" : "12",
      "lock_mode" : "X,REC_NOT_GAP",
      "blocker_state" : "LOCK WAIT",
      "blocker_age" : 300,
      "blocker_rows_locked" : 20,
      "blocker_host" : "192.168.1.100:54321",
      "blocker_command" : "Sleep",
      "blocker_thread_id" : 20,
      "blocker_pid" : 4834469,
      "blocker_rows_modified" : 1,
      "blocker_current_sql" : [ "UPDATE t_lock_test SET val = 'middle' WHERE id = 3" ]
    }
  }
}

SDK Sample Code

The SDK sample code is as follows.

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package com.huaweicloud.sdk.test;

import com.huaweicloud.sdk.core.auth.ICredential;
import com.huaweicloud.sdk.core.auth.BasicCredentials;
import com.huaweicloud.sdk.core.exception.ConnectionException;
import com.huaweicloud.sdk.core.exception.RequestTimeoutException;
import com.huaweicloud.sdk.core.exception.ServiceResponseException;
import com.huaweicloud.sdk.gaussdb.v3.region.GaussDBRegion;
import com.huaweicloud.sdk.gaussdb.v3.*;
import com.huaweicloud.sdk.gaussdb.v3.model.*;


public class ShowLockWaitSessionSolution {

    public static void main(String[] args) {
        // The AK and SK used for authentication are hard-coded or stored in plaintext, which has great security risks. It is recommended that the AK and SK be stored in ciphertext in configuration files or environment variables and decrypted during use to ensure security.
        // In this example, AK and SK are stored in environment variables for authentication. Before running this example, set environment variables CLOUD_SDK_AK and CLOUD_SDK_SK in the local environment
        String ak = System.getenv("CLOUD_SDK_AK");
        String sk = System.getenv("CLOUD_SDK_SK");
        String projectId = "{project_id}";

        ICredential auth = new BasicCredentials()
                .withProjectId(projectId)
                .withAk(ak)
                .withSk(sk);

        GaussDBClient client = GaussDBClient.newBuilder()
                .withCredential(auth)
                .withRegion(GaussDBRegion.valueOf("<YOUR REGION>"))
                .build();
        ShowLockWaitSessionRequest request = new ShowLockWaitSessionRequest();
        request.withInstanceId("{instance_id}");
        request.withNodeId("{node_id}");
        try {
            ShowLockWaitSessionResponse response = client.showLockWaitSession(request);
            System.out.println(response.toString());
        } catch (ConnectionException e) {
            e.printStackTrace();
        } catch (RequestTimeoutException e) {
            e.printStackTrace();
        } catch (ServiceResponseException e) {
            e.printStackTrace();
            System.out.println(e.getHttpStatusCode());
            System.out.println(e.getRequestId());
            System.out.println(e.getErrorCode());
            System.out.println(e.getErrorMsg());
        }
    }
}
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# coding: utf-8

import os
from huaweicloudsdkcore.auth.credentials import BasicCredentials
from huaweicloudsdkgaussdb.v3.region.gaussdb_region import GaussDBRegion
from huaweicloudsdkcore.exceptions import exceptions
from huaweicloudsdkgaussdb.v3 import *

if __name__ == "__main__":
    # The AK and SK used for authentication are hard-coded or stored in plaintext, which has great security risks. It is recommended that the AK and SK be stored in ciphertext in configuration files or environment variables and decrypted during use to ensure security.
    # In this example, AK and SK are stored in environment variables for authentication. Before running this example, set environment variables CLOUD_SDK_AK and CLOUD_SDK_SK in the local environment
    ak = os.environ["CLOUD_SDK_AK"]
    sk = os.environ["CLOUD_SDK_SK"]
    projectId = "{project_id}"

    credentials = BasicCredentials(ak, sk, projectId)

    client = GaussDBClient.new_builder() \
        .with_credentials(credentials) \
        .with_region(GaussDBRegion.value_of("<YOUR REGION>")) \
        .build()

    try:
        request = ShowLockWaitSessionRequest()
        request.instance_id = "{instance_id}"
        request.node_id = "{node_id}"
        response = client.show_lock_wait_session(request)
        print(response)
    except exceptions.ClientRequestException as e:
        print(e.status_code)
        print(e.request_id)
        print(e.error_code)
        print(e.error_msg)
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package main

import (
	"fmt"
	"github.com/huaweicloud/huaweicloud-sdk-go-v3/core/auth/basic"
    gaussdb "github.com/huaweicloud/huaweicloud-sdk-go-v3/services/gaussdb/v3"
	"github.com/huaweicloud/huaweicloud-sdk-go-v3/services/gaussdb/v3/model"
    region "github.com/huaweicloud/huaweicloud-sdk-go-v3/services/gaussdb/v3/region"
)

func main() {
    // The AK and SK used for authentication are hard-coded or stored in plaintext, which has great security risks. It is recommended that the AK and SK be stored in ciphertext in configuration files or environment variables and decrypted during use to ensure security.
    // In this example, AK and SK are stored in environment variables for authentication. Before running this example, set environment variables CLOUD_SDK_AK and CLOUD_SDK_SK in the local environment
    ak := os.Getenv("CLOUD_SDK_AK")
    sk := os.Getenv("CLOUD_SDK_SK")
    projectId := "{project_id}"

    auth, err := basic.NewCredentialsBuilder().
        WithAk(ak).
        WithSk(sk).
        WithProjectId(projectId).
        SafeBuild()

    if err != nil {
        fmt.Println(err)
        return
    }

    hcClient, err := gaussdb.GaussDBClientBuilder().
         WithRegion(region.ValueOf("<YOUR REGION>")).
         WithCredential(auth).
         SafeBuild()


    if err != nil {
        fmt.Println(err)
        return
    }

    client := gaussdb.NewGaussDBClient(hcClient)

    request := &model.ShowLockWaitSessionRequest{}
	request.InstanceId = "{instance_id}"
	request.NodeId = "{node_id}"
	response, err := client.ShowLockWaitSession(request)
	if err == nil {
        fmt.Printf("%+v\n", response)
    } else {
        fmt.Println(err)
    }
}

For SDK sample code of more programming languages, see the Sample Code tab in API Explorer. SDK sample code can be automatically generated.

Status Code

For details, see Status Codes.

Error Code

For details, see Error Codes.