There are three types of Models that can be defined at the time of creating models for your IoT applications. The three models are:
- DataModel
- ThingModel
- AppModel
See Models for details.
Model lifecycle consists of three steps
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System Attribute Name | Description | Persisted | Query Constraint? |
|---|---|---|---|
| Version | Version number of the attribute. This number is automatically incremented each time the value changes. No historical data is persisted. Only the last value is persisted. | Yes | No. You can request the value using Format on <Find> |
| Value | The value of the attribute is stored in "Value". This is specified by user at time of create/save query | Yes | Yes |
| Timestamp | Unix epoch time at the time (in millisecond) of the attribute creation. For example: Timestamp value1457663102004 is same as Fri, 11 Mar 2016 02:25:02 GMTNote that this is only the "Create" timestamp. If attributes are updated their timestamp do not change. | Yes | No |
| QName | Fully qualified name of the attribute. <NamSpace>.<Domain>.<ModelName>.<AttributeName>. For example SimpleModel.MyModels.VendorInfo.vendorName given that VendorInfo is defined within Namespace - SimpleModel, with Domain as MyModels and DataModel Name as VendorInfo | Yes | No |
| Known | Applicable to ThingFacet/AppFacet. Known is the value that is set within the Action. Known can not be set using Create / Update TQL Query by the user. | Yes | No |
| FName | Given name of the attribute name. | Yes | No |
| Datetime | Formatted data time value of the attribute creation. For example:2016-03-10 18:25:02.004 Note that is is only the "Create" Datetime. If attributes are updated their datetime value do not change. | Yes | No |
| Status | This is transient attribute returned as part of the result of TQL Create/Save, Update and Delete operations | No | No. |
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