Patent attributes
Modifying a portion of an XML document stored in a relational database includes converting operations on the document into an operator tree. The operator tree includes a first operator corresponding to a first portion of the schema for the modified data and a second operator corresponding to a parent portion of the schema for the modified data. A first and a second portion of the schema are extracted from the overall document schema. A first validation of the modified data using the first operator with the first portion of the schema is performed. This forms a partially validated XML document portion. Next, a second validation of the partially validated XML document portion with the second portion of the schema is performed using the second operator. The XML document constraints are verified and the modified data is merged into the XML document, thus avoiding a full validation of the XML document when certain XML Schema types are absent in the modified data.