This example requests a simple layered filter, a person has a pet and the pet has a schedule.

Example 1: Get PersonType.LastName, AnimalType.Name, ScheduleType.Period where the Person Has a Pet and that Pet Has a Schedule.

The NodeTypeDescription parameters used in the example are described in Table B.3.

Table B.3 – Example 1 NodeTypeDescription

Type Definition Node

Include

Subtypes

QueryDataDescription

Relative Path

Attribute

Index Range

PersonType

FALSE

“.12:LastName”

value

N/A

“<12:HasPet>12:AnimalType. 12:Name”

value

N/A

“<12:HasPet>12:AnimalType<12:HasSchedule> 12:Schedule. 12:Period”

value

N/A

The corresponding ContentFilter is illustrated in Figure B.5.

image047.png

Figure B.5 – Example 1 Filter

Table B.4 describes the ContentFilter elements, operators and operands used in the example.

Table B.4 – Example 1 ContentFilter

Element[]

Operator

Operand[0]

Operand[1]

Operand[2]

Operand[3]

1

RelatedTo

AttributeOperand = NodeId: PersonType,

BrowsePath “.”, Attribute: NodeId

ElementOperand = 2

AttributeOperand = NodeId: HasPet, BrowsePath “.”, Attribute: NodeId

LiteralOperand = ‘1’

2

RelatedTo

AttributeOperand = NodeId: AnimalType, BrowsePath “.”, Attribute: NodeId

AttributeOperand = NodeId: ScheduleType, BrowsePath “.”, Attribute: NodeId

AttributeOperand = NodeId: HasSchedule, BrowsePath “.”, Attribute: NodeId

LiteralOperand= ‘1’

Table B.5 describes the QueryDataSet that results from this query if it were executed against the instances described in Figure B.4

Table B.5 – Example 1 QueryDataSets

NodeId

TypeDefinition

NodeId

RelativePath

Value

12:30 (JFamily1)

PersonType

“.12:LastName”

Jones

“<12:HasPet>12:AnimalType. 12:Name”

Rosemary

Basil

“<12:HasPet>12:AnimalType<12:HasSchedule> 12:Schedule.12:Period”

Hourly

Daily

12:42(HFamily1)

PersonType

“.12:LastName”

Hervey

“<12:HasPet>12:AnimalType. 12:Name”

Oliver

“<12:HasPet>12:AnimalType<12:HasSchedule> 12:Schedule.12:Period”

Daily

NOTE The RelativePath column and browse name (in parentheses in the NodeId column) are not in the QueryDataSet and are only shown here for clarity. The TypeDefinition NodeId would be an integer not the symbolic name that is included in the table.

The Value column is returned as an array for each Node description, where the order of the items in the array would correspond to the order of the items that were requested for the given Node Type. In Addition, if a single Attribute has multiple values then it would be returned as an array within the larger array, for example in this table Rosemary and Basil would be returned in a array for the .<HasPet>.AnimalType.Name item. They are show as separate rows for ease of viewing. The actual value array for JFamily1 would be (“Jones”, {“RoseMary”, ”Basil”}, {“Hourly”, “Daily”})