Annex B (informative) ContentFilter and Query examples

B.1 Simple ContentFilter examples

B.1.3 Example 2

As another example a filter to select all SystemEvents (including derived types) that are contained in the Area1 View or the Area2 View would result in a logic tree as shown in Figure B.2 and a ContentFilter as shown in Table B.2.

Figure B.2 – Filter logic tree example

Table B.2 describes the elements, operators and operands used in the example.

Table B.2 – ContentFilter example

Element[]	Operator	Operand[0]	Operand[1]
0	And	ElementOperand = 1	ElementOperand = 4
1	Or	ElementOperand = 2	ElementOperand = 3
2	InView	AttributeOperand = NodeId: Area1, BrowsePath: “.”, Attribute: NodeId
3	InView	AttributeOperand = NodeId: Area2, BrowsePath: “.”, Attribute: NodeId
4	OfType	AttributeOperand = NodeId: SystemEventType, BrowsePath: “.”, Attribute: NodeId”