Entities: Understanding Property Types

In the DataModel of our system, entities are composed of various properties, each serving a unique purpose to accurately model and manage data within applications. These properties are derived from a base Property class, encompassing common characteristics crucial for data integrity and system functionality.

Common Property Attributes

All property types share foundational attributes, establishing a consistent framework for data representation:

LogicalId: A unique identifier for the property.
DataType: The type of data (e.g., String, Integer, Boolean) the property holds.
Description: A brief description of the property's purpose.
Required: Indicates whether the property must be provided.
IsUnique: Ensures the property value is unique across all instances.
AutoGenerate: Specifies if the property value is automatically generated by the system.

Specific Property Attributes and Examples

ArrayProperty

Represents an array of objects defined by a custom object type.

{
  "ObjectTyeLogicalId": "CustomObjectTypeId"
}

BooleanProperty

Stores a Boolean value, optionally with a default setting.

{
  "DefaultValue": true
}

CharProperty

Holds a single character, allowing an optional default character.

{
  "DefaultValue": "A"
}

DateTimeProperty

Manages date and time information, with optional format specifications.

{
  "DateAndTime": true,
  "Format": "YYYY-MM-DD HH:mm:ss"
}

DecimalProperty

Handles decimal numbers, allowing for minimum, maximum, default values, and format specification.

{
  "MinValue": 1.0,
  "MaxValue": 100.0,
  "DefaultValue": 50.0,
  "Format": "#.##"
}

DoubleProperty

Stores double-precision floating-point numbers with constraints on values and format.

{
  "MinValue": -100.0,
  "MaxValue": 100.0,
  "DefaultValue": 0.0,
  "Format": "#.##"
}

EnumProperty

Links to a defined enumeration type.

{
  "EnumTyeLogicalId": "StatusEnum"
}

GuidProperty

Stores globally unique identifiers, with an optional default value.

{
  "DefaultValue": "00000000-0000-0000-0000-000000000000"
}

Int16Property, Int32Property, Int64Property

Represent integers of various sizes, including range and default value specifications.

{
  "MinValue": -32768,
  "MaxValue": 32767,
  "DefaultValue": 0
}

PrimitiveArrayProperty

Defines an array of primitive types with a specified element type.

{
  "ValueType": "string"
}

ObjectProperty

Represents a custom object type.

{
  "ObjectTyeLogicalId": "CustomObjectTypeId"
}

StringProperty

Stores text data, with limitations on length and optional default values.

{
  "MaxLength": 255,
  "DefaultValue": "default text",
  "RegularExpression": "[A-Za-z]+"
}

UInt16Property, UInt32Property, UInt64Property

Similar to their signed counterparts but store unsigned integers, with defined ranges and default values.

{
  "MinValue": 0,
  "MaxValue": 65535,
  "DefaultValue": 123
}

TimeSpanProperty

Represents a time interval, with an optional default value.

{
  "DefaultValue": "01:00:00"
}

Each property type is designed with specific attributes to cater to diverse data modeling needs, enhancing the flexibility and precision of the DataModel in applications.

Example Entity

The following JSON snippet provides an example of how these properties might be used within an entity definition:

{
  "Entities": [
    {
      "LogicalId": "Author",
      "Description": "Represents an author of posts.",
      "Properties": [
        {
          "LogicalId": "Id",
          "DataType": "Guid",
          "Description": "Unique identifier for the Author.",
          "Required": true,
          "IsUnique": true,
          "AutoGenerate": true
        },
        {
          "LogicalId": "Name",
          "DataType": "String",
          "Description": "Name of the Author.",
          "Required": true,
          "IsUnique": false,
          "AutoGenerate": false,
          "MaxLength": 255
        },
        {
          "LogicalId": "IsActive",
          "DataType": "Boolean",
          "Description": "Whether the Author is active or not.",
          "Required": true,
          "IsUnique": false,
          "AutoGenerate": false,
          "DefaultValue": true
        }
      ]
    }
  ]
}

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