This simple type specifies the relationship ID in a part's relationship item which is the target of an explicit relationship from the parent XML element. This simple type is an exact analog of ST_RelationshipId defined in the http://schemas.openxmlformats.org/officeDocument/2006/relationships namespace

The type of relationship which shall be the target of the relationship specified shall be determined based on the context of the parent XML element.

[Example: Consider the following markup in an Office Open XML document:

<… o:relid="rId5" />

The relid attribute is of type ST_RelationshipID, and therefore the relationship with ID rId5 shall be the target of an explicit relationship from the source part, based on the context of the parent XML element. end example]

This simple type's contents are a restriction of the XML Schema string datatype.

The following XML Schema fragment defines the contents of this simple type:

<simpleType name="ST_RelationshipId">

   <restriction base="xsd:string"/>

</simpleType>