EquiX Easy Querying in XML Databases

The Web is explored by many users, but only a few of them have experience in using query languages. Thus, one of the greatest challenges, provided by XML, is to create a query language simple enough for the naive user. In this paper, we present EquiX|a powerful and easy to use query language for XML. The main goal in designing EquiX is to strike the right balance between expressive power and simplicity. EquiX has a form-based GUI that is constructed automatically from the DTDs of XML documents. Query forms are built from well known HTML primitives. The result of a query in EquiX is a collection of XML documents, and it is automatically generated from the query without explicit speci cation of the format of the result. Knowledge of XML syntax is not required in order to use EquiX. Yet, EquiX is able to express rather complicated queries, containing quanti cation, negation and aggregation. We present the data model in Section 2. In Sections 3, and 4 we introduce the query language syntax, and semantics. Automatic generation of query results is discussed in Section 6. In Section 7, we review related work and conclude.