Abstract: A database server registers an XML schema and determines a database representation for the XML schema and mapping information, determining what database types should be used to represent an XML schema and/or how instances of the XML schema are stored by a database system. The mapping information indicates the mapping between the constructs declared in the XML schema and the constructs included in the appropriate database representation. The XML schema may contain annotations that describe one or more properties of a database representation of an XML date-time type. Based on the annotations, the database determines an appropriate database representation and generates mapping information mapping the declaration of the XML date-time type of the XML schema to the constructs of the database representation.

Abstract: Systems, methods, and other embodiments associated with providing an XML-based translation service are described. One method embodiment includes accessing a translation-aware XML document that may comply with a translation-enabling XML schema. The document may store a first XML element that stores translatable data and a second XML element that stores a translation of the translatable data. The schema may describe that the first XML element includes a first identifier that identifies the first element as storing translatable data. The schema may also describe that the second XML element includes a second identifier that identifies the second element as storing a translation for translatable data. The method may also include establishing a session language identifier and providing a virtual view of the translation-aware XML document, the virtual view being determined, at least in part, by the session language identifier.

Abstract: A method and apparatus is provided for translating queries, such as path expressions and SQL/XML constructs, into SQL statements to be executed against an XML index, which improves processor time as opposed to applying path expressions directly to the original XML documents to extract the desired information. Simple path expressions, filter expressions, descendant axes, wildcards, logical expressions, relational expressions, literals, and other path expressions are all translated into SQL for efficient querying of an XML index. Similarly, rules for translating SQL/XML constructs into SQL are provided.

Abstract: Systems, methods, and other embodiments associated with providing query modes for translation-enabled XML documents are described. One method embodiment includes receiving an XPath query to an XML document that may store a translation for a data element. The method embodiment may also include automatically selecting a query mode for the XPath query. The method embodiment may also include querying the XML document using the XPath query and the selected query mode. The query mode may control, at least in part, the operation of an XML database logic.

Abstract: A method and system for evolving XML-schema-based data to conform to an evolved XML schema is disclosed. Based on an existing XML schema and an instance document that is based on the existing XML schema, an XML-schema-independent form of the instance document is generated. Based on a set of specified transformations and the XML-schema-independent form of the instance document, an evolved instance document is generated. The evolved instance document conforms to an evolved XML schema that incorporates changes to the existing XML schema. Techniques described herein are flexible enough to accommodate a wide variety of evolutions to XML schemas.

Abstract: A method and apparatus for efficiently processing a query that specifies a location path and a content path is provided. The location path identifies the hierarchical location of a set of documents within a resource hierarchy. The content path identifies hierarchical location of one or more nodes within the content of the set of documents. Computing the query includes using a resource hierarchy index, based on the location path, to generate first results corresponding to the set of documents. Computing the query also includes using a content index, based on the content path, to generate second results corresponding to the one or more nodes. Final results of the query are based on the first results and second results by, for example, joining the first and second results.

Abstract: Techniques for efficiently processing a query are provided. A query may specify a location path and a content path. The location path identifies the hierarchical location of a set of documents within a resource repository. The content path identifies hierarchical location of one or more nodes within the content of the set of documents. Computing the query includes using a repository index, based on the location path and the content path, to generate first results corresponding to the set of documents and second results corresponding to the one or more nodes. Final results of the query are based on the first results and second results. Another technique is provided for formatting a locator value in the repository index to support data that is stored object-relationally. Another technique is provided for storing index information about virtual content.

Abstract: Techniques are provided for transporting subset of databases containing binary XML data. In one embodiment, a method is provided that allows transporting binary XML data that conforms to schema by also transporting the schema entries that are necessary to derive the binary XML. In another embodiment, a method is provided that allows transporting binary XML data that does not conform to schema by also transporting the token tables that contain the mapping for the binary XML.

Abstract: Described is a hierarchical index that captures the hierarchical relationship of a hierarchy emulated by a relational database system. The hierarchical index is implemented, using a database table which contains rows that serve as entries of the hierarchical index. Another table has rows that are associated with nodes in the hierarchy. Each entry in the hierarchal index maps to a row that corresponds to a node in the hierarchy. A node in the hierarchy may be a parent node with one or more child nodes. In this case, the corresponding entry in the hierarchical index contains identifiers which identify other entries in the index, where the other entries correspond to rows associated with child nodes of the parent node.

Abstract: A method and system are provided for extracting a valid, self-contained fragment for a node in a XML document stored in a database management system. An XML index is used to identify a location in which XML fragment data corresponding to the node is located. Ancestors of the node are identified and examined for any information needed for the proper interpretation of the fragment. If an ancestor node contains such needed information, this information is patched into the XML fragment to ensure that the fragment is a valid, self-contained XML fragment.

Abstract: Techniques are described for preserving the original insignificant white space of XML data. The techniques may be used in combination with compact XML data storage formats, such as binary XML, to preserve the insignificant white space without requiring as much storage space as uncompressed formats. White space opcodes/operand pairs are described for representing white space characters and white space patterns. The white space opcode/operand pairs represent the white space in binary XML, are use to generate the original white space when the binary XML is decoded back to textual XML data.

Abstract: Various techniques are described hereafter for improving the efficiency of binary XML encoding and loading operations. In particular, techniques are described for incrementally encoding XML in response to amount-based requests. After encoding enough binary XML to satisfy an amount-based request, the encoder stops encoding the XML until a subsequent request is received. The incremental encoding may take place on the client-side or the server-side. Techniques are also described for reducing the character set conversion operations by having a parser convert tokens in text XML into one character set while converting non-token text in the text XML into another character set. Techniques are also described for generating self-contained binary XML documents, and for improving remap operations by providing a binary XML document on a chunk-by-chunk basis.

Abstract: Techniques are provided for incrementally maintaining an XML index built to access XML data that is encoded in binary XML form. Rather than delete and reinsert index entries of all the nodes of a modified XML document, only the index entries of the affected nodes are modified. Consequently, the order key values stored in the index may become inconsistent with the current hierarchical locations of the nodes to which the order key values correspond. Techniques are described for resolving the inconsistencies, and for addressing additional problems that result when the XML index is path-subsetted.

Abstract: A method and apparatus for validating XML documents in a streaming fashion is provided. A streaming validator validates an XML document by comparing the contents of the XML document to an XML schema. Tokens are generated for each element or attribute of the XML schema and for each element or attribute of the XML document using the same generator token function. The elements and attributes of the XML document and XML schema are compared using tokens rather than string comparisons to perform the validation more efficiently.

Abstract: A method and apparatus for estimating the cost of streaming evaluation of XPaths is provided. Aggregate statistics are maintained by the database server upon initiation of a database function by the database administrator about the nodes of the XML document. Based upon these statistics and the complexity of the particular XPath query, an estimate of the cost of the query, in time and computing resources required, is computed.

Abstract: A method is provided to efficiently evaluate an expression to determine the partition key for an XML document stored in a database without the entire XML document first being stored in temporary memory storage. The partition key is determined using streaming evaluation or incrementally using a DOM node tree as a portion of the document is read and stored in the buffer. The XML document is stored in the partition using the read portion of the document stored in the buffer and the remaining portion from the original source.

Abstract: In-place XML schema evolution occurs by evaluating an existing XML schema in a database system to see if it is compatible with a new XML schema. To determine if the old schema is compatible with the new schema, a lock-step traversal is performed on the two schemas. Each instruction in the old schema is compared to instructions in the new schema. Detected differences between the two schemas are evaluated to determine if existing XML documents are still compatible with the new schema. If they are, then an in-place schema evolution operation can take place. The in-place schema operation basically, involves appending the updated object information to the underlying object type and preserving the order of elements in a document by storing element mapping information on disk.

Abstract: XML schema evolutions can be performed on an XML-type database using partial data copy techniques. The partial data copy techniques provide mechanisms to identify a minimal set of data in the database that needs be copied out in order for schema evolution operations to occur. Identifying the minimal set of data involves comparing an existing XML schema to a new XML schema and determining the differences between the two schemas. Based on those differences, a minimal set of data can be determined. That data can then be copied to a temporary storage location, while the XML schema and its associated database structure are updated to conform to the new XML schema. Then, the minimal set of data is copied back into the modified database structure.

Abstract: Techniques manage the presence of repeated constructs within a complex type at the time of schema registration. At registration, techniques detect repeated elements in the XML schema and analyze whether the repeated elements are from the same complex type. If so, techniques perform additional analysis to determine a minimal common ancestor. Within the context of a minimal common ancestor, techniques determine the maximum number of times an element may occur in the schema. In a choice content model, the largest maximum occurrence value is selected. In other content models, the maximum occurrence value is determined by adding together the occurrence values for the repeated elements. Then, when an object relational table is generated for the XML schema, the maximum number of times that an element appears in the schema is this value. Techniques retain the advantages of object relational storage, even after a schema evolution.

Abstract: Populating an XML index is parallelized, providing both inter-document and intra-document parallelism, by using multiple pull-type parser processes to parse respective XML documents in parallel and to call respective ‘instances’ of the function that generates the index entries based on parsed XML node information. The function is configured to operate according to a cursor-type interface model, whereby each function instance can operate on one node at a time in a controlled pull manner rather than in an uncontrolled streaming manner. Hence, the index load procedure flow can be in the control of an application or routine, via the pull parsers, rather than in the control of a serial stream-based parser.