====== Orbit Resource Descriptor =====


ORD stands for Orbit Resource Descriptor. This is an extension file that can accompany any spatial storage format.

===== Structure =====

As the name says, it describes the resource and adds information to it. For example, it can add the following information: 
  * [[2210:desktop:dataset:contents:join|Joined Tables]]: an extra attribute table file and link it to the resource attributes by specifying the relationship.
  * [[2210:desktop:dataset:index|Scale Limits]]: it is possible to set a scale range (or only a max or min) where the layer is visible.
  * [[2210:technology:core:crs|CRS]]: information about the coordinate system and datum
  * [[2210:desktop:dataset:contents:naming| Naming ]]: information about the user name, attributes containing hyperlinks, attributes containing annotations, primary fields, map tip fields.
  * [[2210:desktop:dataset:contents:index#rules| Rules ]]: information about attribute rules defined by a formula or a value list
  * Username: This is the name of the dataset as displayed in the Dataset List

===== Create and Edit =====

Create and edit these files using a text editor. Take care of spelling and file syntax. \\

===== Examples =====

Below are some ORD snippets that demonstrate how each type of information is stored.

==== Joined Tables ====

<code bash>
AttributeJoin=
 ModelId=1
 SourceTableName=D:\head_state.dbf
 TargetSetId=2
 TargetSetName=Head_State
 TargetSetDescription=
 JoinedField=
  AttributeSetName=Attributes
  AttributeName=NAME
  ColumnName=STATE
AttributeJoin=
 ModelId=1
 SourceTableName=<RESOURCELOCATION>\population.txt
 TargetSetId=3
 TargetSetName=Population
 TargetSetDescription=
 JoinedField=
  AttributeSetName=Attributes
  AttributeName=NAME
  ColumnName=STATE
</code>

==== Scale Limits ====

<code bash>
ScaleLimits=
 Smallest=1000.0
 Largest=50.0
</code>

==== DataSet CRS ====

<code bash>
DataSetCRS=4326
 VerticalCRS=5710
</code>


==== Naming ====

<code bash>
AttributeContentType=
 ModelId=1
  AttributeSetName=Attributes
   AttributeName=ID
    AttributeContentType=url-prefix
   AttributeName=Web
    AttributeContentType=url-prefix=http://;url;url-suffix=.com;active-hyperlink
</code>

<code bash>
PrimaryAttribute=
 ModelId=1
  AttributeSetName=Attributes
  AttributeName=ID
</code>

<code bash>
MapTipAttribute=
 ModelId=1
  AttributeSetName=Attributes
  AttributeName=NAME
</code>

==== Rules ====

=== Valuelist ===
 
<code bash>
AttributeConstraint=
 ModelId=1
  AttributeSetName=Attributes
   AttributeName=Type
    Rule=valuelist
    Value=CM
     Label=Constitutional monarchy
    Value=CR
     Label=Constitutional republic
    Value=AM
     Label=Absolute monarchy
</code>

=== Formula ===

<code bash>
AttributeConstraint=
 ModelId=1
  AttributeSetName=Attributes
   AttributeName=Area
    Rule=expression
    Expression=Area()
</code>

=== Attribute Dependent Valuelist ===

<code bash>
AttributeConstraint=
 ModelId=1
  AttributeSetName=Attributes
   AttributeName=Municipality
    Rule=attribute-dependent-valuelist
    DependentAttribute=city
    Value=
     DependentAttributeValue=Antwerp
     Value=Antwerpen
     Value=Berchem
     Value=Borgerhout
    Value=
     DependentAttributeValue=Brussels
     Value=Anderlecht
     Value=Oudergem
     Value=Sint-Agatha-Berchem
</code>

=== Attribute Set Rules ===

<code bash>
ShouldHaveAttributeSets=
 ModelId=1
  AttributeSetName=Attributes
   ShouldHaveAttributeSets=true
</code>

==== Username ====

<code bash>
DataSetUserName=World Countries
</code>

<code bash>
AttributeSetUserNames=
 ModelId=1
  AttributeSetName=Attributes
   AttributeSetUserName=Attributes
DataSetUserName=World Countries
ModelUserNames=
 ModelId=1
  ModelUserName=Model
  ModelUserDescription=
</code>