The Graphical Query panel

This topic provides a brief guide to the functionality of the Graphical Query panel of the Semantic Search Engine interface. The Graphical Query constitutes the top section of the Query Pane and consists, from top to bottom, of a menu bar containing the Query toolbar, the Query panel, the Refinements panel and the Submit Semantic Query button.

The Query toolbar

The query toolbar is depicted in the following picture:

The various icons in the toolbar are explained next:

	Intersection :	Creates an intersection node as the parent of the selected node, allowing for the creation of other nodes as siblings to the selected node and thus substituting the selected node with a multitude of terms forming a logical AND construct.
	Union:	Creates a union node as the parent of the selected node, allowing for the creation of other nodes as siblings to the selected node and thus substituting the selected node with a multitude of terms forming a logical OR construct.
	Complement:	Creates a complement node as the parent of the selected node, thus logically negating the selected node in the tree and forming a logical NOT construct.
	Delete:	Removes the selected node in the query tree.

Each icon may be enabled or disabled at any moment depending on the selected node in the query tree. For example, if the root node of the tree is selected, the Delete icon is deactivated as the root node may not be removed.

For a description of how the query toolbar is used in refer to Query Formulation in the Introduction section.

The Query panel

The Query panel section of the Query Pane is shown in the picture below:

Each query is represented by a tree depicted in the query panel. The nodes in the tree represent specific restrictions on the query. A query can be refined by adding constraints on the currently selected node. The available refinements for the selected node are displayed in the Refinements panel.

Node icons

There are several icons displayed before nodes in the query tree. They are explained below:

	Tree root:	The root of the query tree. This node does not play any particular role in the query.
	Query root:	The root of the query. This node represents what the query is about and defines the type of the results. All other nodes in the query refine the concept captured by this node.
	Some values from:	Signifies that the node to which it applies represents a "has some values from" constraint.
	Has value:	Signifies that the node to which it applies represents a "has value" constraint.
	Minimum cardinality:	Signifies that the node to which it applies represents a "minimum cardinality" constraint.
	Maximum cardinality:	Signifies that the node to which it applies represents a "maximum cardinality" constraint.
	Cardinality:	Signifies that the node to which it applies represents an "cardinality" constraint.
	Same as:	Signifies that the node to which it applies represents a "same as" constraint.
	Different from:	Signifies that the node to which it applies represents a "different from" constraint.
	Greater than:	Signifies that the node to which it applies represents a "greater than" constraint.
	Less than:	Signifies that the node to which it applies represents a "less than" constraint.

For a description of the various constraints refer to Property Restrictions.

The Refinements panel

The Refinements panel section of the Query Pane is shown in the picture below:

The nodes in the tree represent properties associated with the concept captured by the currently selected node in the Query panel. Nodes in the Refinements tree can be arranged hierarchically. Thus, a node representing a specific property may have sub-nodes associated with it. Each sub-node represents the same property as its parent node but with a different range. The range of the sub-node is a specialization of the range of its parent node.

In the picture above, there is a first level node representing a property named hasElement which has as its range the class PDModel. This node also has a child node with range the class SimplificationModel. In the ontology SimplificationModel is specified to be a subclass (specialization) of PDModel. By choosing as refinement the child node and not the parent node we can specify a constraint that is harder to meet by the search mechanism and therefore obtain more accurate results. On the other hand, if we are unsure whether this constraint can be met (maybe there are no results satisfying it) we can opt for a weaker constraint by choosing the parent node - or no refinement at all.

For a description of properties, their domain and range values refer to Properties.

Node icons

There are several icons displayed before nodes in the refinements tree. They are explained below:

Datatype property:

Signifies that the node to which it applies represents a datatype property.

For a description of datatype properties refer to Properties.

Object property:

Signifies that the node to which it applies represents an object property.

For a description of object properties refer to Properties.

Submit Semantic Query button

The Submit Semantic Query button is used to submit a graphical query and retrieve the results.