SyntaxThe general form of a MATCH is given below.
MATCH(variable, descriptor_regular_expression)The match extends a path (represented by variable) to the edges that match the descriptor regular expression. The only difference between AUCQL and other semistructured query languages is that the descriptors are more complicated in AUCQL since they can involve several properties.
The NAME propertyThe NAME property represents the name of an edge. It is the most commonly used property in matching. Let's start with a simple example to find all the 'movie' edges from a root.
Note that the NAME property is required to be present, so that the query does not match edges that lack a NAME property.
Now let's extend the paths to look for 'review' edges.
Alternatively, we could use the composition in a regular expression to do the MATCH.
The appropriate use of defaults makes this look more like a standard semistructured query.
Other propertiesNAME is just one property in a more general property space. Any property could be used to match.
Multiple PropertiesProperties can also be combined in a descriptor.
Setting default properties is often the most useful way to combine properties.
Curtis E. Dyreson, Michael H. Böhlen, and Christian S. Jensen © 1998-2000. All rights reserved.
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