IFC 4.3.0.0 (IFC4X3) final

8.21.3.2 IfcOwnerHistory

8.21.3.2.1 Semantic definition

IfcOwnerHistory defines all history and identification related information. In order to provide fast access it is directly attached to all independent objects, relationships and properties.

IfcOwnerHistory is used to identify the creating and owning application and user for the associated object, as well as capture the last modifying application and user.

Informal Propositions:

  1. If LastModifiedDate is defined but ChangeAction is not asserted, then the state of ChangeAction is assumed to be UNDEFINED.
  2. If both LastModifiedDate and ChangeAction are asserted, then the state of ChangeAction applies to the value asserted in LastModifiedDate.

8.21.3.2.2 Entity inheritance

8.21.3.2.3 Attributes

# Attribute Type Description
IfcOwnerHistory (8)
1 OwningUser IfcPersonAndOrganization

Direct reference to the end user who currently "owns" this object. Note that IFC includes the concept of ownership transfer from one user to another and therefore distinguishes between the Owning User and Creating User.

2 OwningApplication IfcApplication

Direct reference to the application which currently "owns" this object on behalf of the owning user of the application. Note that IFC includes the concept of ownership transfer from one application to another and therefore distinguishes between the Owning Application and Creating Application.

3 State OPTIONAL IfcStateEnum

Enumeration that defines the current access state of the object.

4 ChangeAction OPTIONAL IfcChangeActionEnum

Enumeration that defines the actions associated with changes made to the object.

5 LastModifiedDate OPTIONAL IfcTimeStamp

Date and Time expressed in UTC (Universal Time Coordinated, formerly Greenwich Mean Time or GMT) at which the last modification was made by LastModifyingUser and LastModifyingApplication.

6 LastModifyingUser OPTIONAL IfcPersonAndOrganization

User who carried out the last modification using LastModifyingApplication.

7 LastModifyingApplication OPTIONAL IfcApplication

Application used to make the last modification.

8 CreationDate IfcTimeStamp

The date and time expressed in UTC (Universal Time Coordinated, formerly Greenwich Mean Time or GMT) when first created by the original OwningApplication. Once defined this value remains unchanged through the lifetime of the entity.

Table 8.21.3.2.S

8.21.3.2.4 Formal propositions

Name Description
CorrectChangeAction

If ChangeAction is asserted and LastModifiedDate is not defined, ChangeAction must be set to NOTDEFINED

(EXISTS(LastModifiedDate)) OR
(NOT(EXISTS(LastModifiedDate)) AND NOT(EXISTS(ChangeAction))) OR
(NOT(EXISTS(LastModifiedDate)) AND EXISTS(ChangeAction) AND ((ChangeAction = IfcChangeActionEnum.NOTDEFINED) OR (ChangeAction = IfcChangeActionEnum.NOCHANGE)))
Table 8.21.3.2.T

8.21.3.2.5 Examples

8.21.3.2.6 Formal representation

ENTITY IfcOwnerHistory;
	OwningUser : IfcPersonAndOrganization;
	OwningApplication : IfcApplication;
	State : OPTIONAL IfcStateEnum;
	ChangeAction : OPTIONAL IfcChangeActionEnum;
	LastModifiedDate : OPTIONAL IfcTimeStamp;
	LastModifyingUser : OPTIONAL IfcPersonAndOrganization;
	LastModifyingApplication : OPTIONAL IfcApplication;
	CreationDate : IfcTimeStamp;
 WHERE
	CorrectChangeAction : (EXISTS(LastModifiedDate)) OR
(NOT(EXISTS(LastModifiedDate)) AND NOT(EXISTS(ChangeAction))) OR
(NOT(EXISTS(LastModifiedDate)) AND EXISTS(ChangeAction) AND ((ChangeAction = IfcChangeActionEnum.NOTDEFINED) OR (ChangeAction = IfcChangeActionEnum.NOCHANGE)));
END_ENTITY;

8.21.3.2.7 References

8.21.3.2.8 Changelog

  • where_rules, CorrectChangeAction
  • attributes ChangeAction is_optional, Changed from False to True