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.
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 |
AttributeOperand = NodeId: PersonType, BrowsePath “.”, Attribute: NodeId |
ElementOperand = 2 |
AttributeOperand = NodeId: HasPet, BrowsePath “.”, Attribute: NodeId |
LiteralOperand = ‘1’ |
|
|
2 |
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”})