> ## Documentation Index > Fetch the complete documentation index at: https://docs.eorion.com/llms.txt > Use this file to discover all available pages before exploring further. # 根据Id获取 > Retrieves a historic variable by id. ## OpenAPI ````yaml GET /history/variable-instance/{id} openapi: 3.0.2 info: title: ORION Platform REST API description: OpenApi Spec for ORION Camunda Platform REST API. version: 7.22.6-ee license: name: Apache License 2.0 url: http://www.apache.org/licenses/LICENSE-2.0.html servers: - url: http://{host}:{port}/{contextPath} description: The API server for the default process engine variables: host: default: localhost port: default: '8080' contextPath: default: engine-rest - url: http://{host}:{port}/{contextPath}/engine/{engineName} description: The API server for a named process engine variables: host: default: localhost port: default: '8080' contextPath: default: engine-rest engineName: default: default - url: '{url}' description: The API server with a custom url variables: url: default: '' security: - basicAuth: [] tags: - name: Authorization - name: Batch - name: Condition - name: Decision Definition - name: Decision Requirements Definition - name: Deployment - name: Engine - name: Event Subscription - name: Execution - name: External Task - name: Filter - name: Group - name: Historic Activity Instance - name: Historic Batch - name: Historic Decision Definition - name: Historic Decision Instance - name: Historic Decision Requirements Definition - name: Historic Detail - name: Historic External Task Log - name: Historic Identity Link Log - name: Historic Incident - name: Historic Job Log - name: Historic Process Definition - name: Historic Process Instance - name: Historic Task Instance - name: Historic User Operation Log - name: Historic Variable Instance - name: History Cleanup - name: Identity - name: Incident - name: Job - name: Job Definition - name: Message - name: Metrics - name: Migration - name: Modification - name: Process Definition - name: Process Instance - name: Signal - name: Schema Log - name: Task - name: Task Attachment - name: Task Comment - name: Task Identity Link - name: Task Local Variable - name: Task Variable - name: Telemetry - name: Tenant - name: User - name: Variable Instance - name: Version externalDocs: description: Find out more about ORION Rest API url: https://docs.eorion.com paths: /history/variable-instance/{id}: get: tags: - Historic Variable Instance summary: Get Variable Instance description: Retrieves a historic variable by id. operationId: getHistoricVariableInstance parameters: - name: id in: path schema: type: string required: true description: The id of the variable instance. - name: deserializeValues in: query schema: type: boolean description: >- Determines whether serializable variable values (typically variables that store custom Java objects) should be deserialized on server side (default `true`). If set to `true`, a serializable variable will be deserialized on server side and transformed to JSON using [Jackson's](https://github.com/FasterXML/jackson) POJO/bean property introspection feature. Note that this requires the Java classes of the variable value to be on the REST API's classpath. If set to `false`, a serializable variable will be returned in its serialized format. For example, a variable that is serialized as XML will be returned as a JSON string containing XML. **Note:** While `true` is the default value for reasons of backward compatibility, we recommend setting this parameter to `false` when developing web applications that are independent of the Java process applications deployed to the engine. responses: '200': content: application/json: schema: $ref: '#/components/schemas/HistoricVariableInstanceDto' examples: example-1: summary: Status 200. description: GET `/history/variable-instance/someId` value: id: someId name: amount type: Integer value: 5 valueInfo: {} processDefinitionKey: aProcessDefinitionKey processDefinitionId: aProcessDefinitionId processInstanceId: aProcessInstanceId executionId: aExecutionId activityInstanceId: Task_1:b68b71ca-e310-11e2-beb0-f0def1557726 caseDefinitionKey: null caseDefinitionId: null caseInstanceId: null caseExecutionId: null taskId: null tenantId: null errorMessage: null state: CREATED createTime: 2017-02-10T14:33:19.000+0200 removalTime: 2018-02-10T14:33:19.000+0200 rootProcessInstanceId: aRootProcessInstanceId description: Request successful. '404': content: application/json: schema: $ref: '#/components/schemas/ExceptionDto' description: >- Variable with given id does not exist. See the [Introduction](https://docs.camunda.org/manual/7.22/reference/rest/overview/#error-handling) for the error response format. components: schemas: HistoricVariableInstanceDto: allOf: - type: object properties: id: type: string nullable: true description: The id of the variable instance. name: type: string nullable: true description: The name of the variable instance. processDefinitionKey: type: string nullable: true description: >- The key of the process definition the variable instance belongs to. processDefinitionId: type: string nullable: true description: >- The id of the process definition the variable instance belongs to. processInstanceId: type: string nullable: true description: The process instance id the variable instance belongs to. executionId: type: string nullable: true description: The execution id the variable instance belongs to. activityInstanceId: type: string nullable: true description: The id of the activity instance in which the variable is valid. caseDefinitionKey: type: string nullable: true description: The key of the case definition the variable instance belongs to. caseDefinitionId: type: string nullable: true description: The id of the case definition the variable instance belongs to. caseInstanceId: type: string nullable: true description: The case instance id the variable instance belongs to. caseExecutionId: type: string nullable: true description: The case execution id the variable instance belongs to. taskId: type: string nullable: true description: The id of the task the variable instance belongs to. tenantId: type: string nullable: true description: The id of the tenant that this variable instance belongs to. errorMessage: type: string nullable: true description: >- An error message in case a Java Serialized Object could not be de-serialized. state: type: string nullable: true description: >- The current state of the variable. Can be 'CREATED' or 'DELETED'. createTime: type: string format: date-time nullable: true description: >- The time the variable was inserted. [Default format](https://docs.camunda.org/manual/7.22/reference/rest/overview/date-format/) `yyyy-MM-dd'T'HH:mm:ss.SSSZ`. removalTime: type: string format: date-time nullable: true description: >- The time after which the variable should be removed by the History Cleanup job. [Default format](https://docs.camunda.org/manual/7.22/reference/rest/overview/date-format/) `yyyy-MM-dd'T'HH:mm:ss.SSSZ`. rootProcessInstanceId: type: string nullable: true description: >- The process instance id of the root process instance that initiated the process containing this variable. - $ref: '#/components/schemas/VariableValueDto' ExceptionDto: title: ExceptionDto type: object properties: type: type: string nullable: true description: An exception class indicating the occurred error. message: type: string nullable: true description: A detailed message of the error. code: type: number description: >- The code allows your client application to identify the error in an automated fashion. You can look up the meaning of all built-in codes and learn how to add custom codes in the [User Guide](https://docs.camunda.org/manual/7.22/user-guide/process-engine/error-handling/#exception-codes). VariableValueDto: type: object properties: value: $ref: '#/components/schemas/AnyValue' type: type: string nullable: true description: The value type of the variable. valueInfo: type: object additionalProperties: true description: >- A JSON object containing additional, value-type-dependent properties. For serialized variables of type Object, the following properties can be provided: * `objectTypeName`: A string representation of the object's type name. * `serializationDataFormat`: The serialization format used to store the variable. For serialized variables of type File, the following properties can be provided: * `filename`: The name of the file. This is not the variable name but the name that will be used when downloading the file again. * `mimetype`: The MIME type of the file that is being uploaded. * `encoding`: The encoding of the file that is being uploaded. The following property can be provided for all value types: * `transient`: Indicates whether the variable should be transient or not. See [documentation](https://docs.camunda.org/manual/7.22/user-guide/process-engine/variables#transient-variables) for more informations. (Not applicable for `decision-definition`, ` /process-instance/variables-async`, and `/migration/executeAsync` endpoints) AnyValue: description: |- Can be any value - string, number, boolean, array or object. **Note**: Not every endpoint supports every type. securitySchemes: basicAuth: type: http scheme: basic ````