The graphical editor supports disjunctions between feature-value
pairs and feature values, but not between graph relations or any
grouped parts of a query (cf. section 7, chapter III).
The graphical query editor
The graphical query editor can be used to create queries without knowledge of the TIGERSearch query language. For example, you can create nodes with a few mouse clicks, and change values by selecting an item from the list of a pull down menu. You can also create edges between nodes, which represent dominance and precedence relations.The graphical query editor is the result of Holger Voormann's diploma thesis ([Voormann2002]; in German).
An alternative to the textual mode
The graphical editor has been designed for beginners as well as for casual users. Power users will likely create queries faster textually than graphically. It is also possible to start constructing a query graphically, automatically generate the textual equivalent, and make some further textual edits.
Graphical vs. textual queries
Because the graphical mode has also been designed for people who want to learn the TIGERSearch query language (cf. chapter III), the graphical construction of a query follows the concept of the textual query language. For example, nodes are specified with an arbitrary number of feature-value pairs.
The graphical query editor as a preprocessor
To process a graphical query, it is necessary to convert it to a textual representation. You can see the textual mode as a plugin, which is converting your graphical query to the TIGERSearch query language (see figure below).
Figure: Before query processing, the graphical construction is converted to a textual query.
Limitations
Because of the architecture (see paragraph above), the graphical mode may, in principle, have the power of the TIGERSearch query language. However, in the current version there are some limitations:
The graphical editor supports disjunctions between feature-value
pairs and feature values, but not between graph relations or any
grouped parts of a query (cf. section 7, chapter III).
It is not possible to create an unspecified node (cf. subsection 4.3).
Variables, used for equality of node specifications, are not yet
supported (cf. subsection 7.2, chapter III).
Templates are not yet supported (cf. section 9, chapter III).