Patent application number | Description | Published |
20090112902 | DOCUMENT FIDELITY WITH BINARY XML STORAGE - Techniques are provided for ensuring lexical fidelity when an XML document is stored in a binary format. Operations, on the XML data, that would cause the loss of lexical fidelity between the original XML document and the binary-encoded version of the XML document are not performed. Such operations include the removal of unnecessary whitespace characters, certain data type conversions, CRLF normalization, the “collapsing” of two-tag empty elements into a single tag empty element, and the replacing of entity references or numeric character references with another value. An XML schema, to which the XML document conforms, may indicate that the XML document is to be stored in a lexical fidelity mode. Additionally, or alternatively, the database statement that (when executed) causes the XML document to be stored in a binary format may so indicate. | 04-30-2009 |
20090150412 | EFFICIENT STREAMING EVALUATION OF XPATHS ON BINARY-ENCODED XML SCHEMA-BASED DOCUMENTS - A database system may utilize XML schema information to increase the efficiency of an XPath streaming evaluation. The database system may access XML schema or translation information during the evaluation of an element, attribute, or value in an XML data source. Based on the XML schema or translation information, the database system may determine matches to an XPath expression without decoding any binary-encoded data in the XML data source. Also, based on the XML schema information, the database may selectively skip or evaluate portions of the XML data source depending on whether those portions are defined in the XML schema so as to possibly contain a match to one or more unmatched steps in the XPath expression. XML schema information may be compiled into a compiled representation of the XPath expression for additional efficiencies. | 06-11-2009 |
20090307239 | FAST EXTRACTION OF SCALAR VALUES FROM BINARY ENCODED XML - Techniques are provided for efficiently extracting scalar values from binary-encoded XML data. Node information is stored in association with binary-encoded XML data to indicate whether one or more nodes of an XML document are simple or complex. A node is simple if the node has no child elements and no attributes. The node information of a particular node is used to determine whether a particular node, identified in a query, is simple or complex. If the particular node is simple, then the scalar value of the particular node is identified without performing any operations other than possibly converting the scalar value to a non-binary-encoded format or converting the scalar value to a value of a different data type. | 12-10-2009 |
20100023478 | Utilizing Path IDs For Name And Namespace Searches - In a database system, names and namespace of XML nodes are computed from path ids. The path ids are constructed from tokens, each of which represents a particular name or namespace-name pair. | 01-28-2010 |
20100030726 | Mechanism For Deferred Rewrite Of Multiple Xpath Evaluations Over Binary XML - A mechanism is provided for improving the performance of particular database queries operating on a view comprising binary-encoded XML. The key to improving performance is to determine whether a XML index is available to improve the computation of XPath data before deriving an optimized execution plan for a particular query. When a XML index is not available to help expedite the computation of binary-encoded XML, then deferring the computation of the XPath data until after the view merge stage avoids unnecessary computation of XPaths that are part of the view but not needed for the particular query. | 02-04-2010 |
20100030727 | Technique For Using Occurrence Constraints To Optimize XML Index Access - Approaches are provided for improving the performance of certain database queries that operate on binary-encoded XML. In particular, the approach uses occurrence and type constraint information about XML data stored in the database for optimizing the relational rewrite of a query. Constraint information can be obtained in several different ways including through a formal language specification such as an XML Schema or DTD, through discovery of a user-provided secondary index on a an XML path table, or through a structural summary that is derived from statistical analysis on a set of XML documents stored in the database. | 02-04-2010 |
20100036825 | Interleaving Query Transformations For XML Indexes - During query optimization, XML index and view merge transformations may be interleaved. | 02-11-2010 |
20100145957 | Estimating Cardinalities of XML Table Constructs Within Queries - Techniques are provided for estimating the cardinality of a virtual result table that is produced by executing path-based table functions within a query, such as the XMLTABLE function. Some path-based table functions apply a path expression to input from a base table of XML documents to select rows to produce the result table. Path statistics are collected for the path expressions for the base table. The path statistics are used to estimate the cardinalities of the result table. The estimated cardinality of the result table is useful for estimating costs of query execution plans that are generated for the query. | 06-10-2010 |
20100235344 | MECHANISM FOR UTILIZING PARTITIONING PRUNING TECHNIQUES FOR XML INDEXES - Techniques are provided for utilizing partition pruning for XML indexes. The computer-implemented method comprises storing XML documents in a document table, which is equi-partitioned with a corresponding index table, and wherein the partitioned document table and the partitioned index table can be searched using a query comprising a partitioning pruning directive. | 09-16-2010 |
20100235348 | LOADING AN INDEX WITH MINIMAL EFFECT ON AVAILABILITY OF APPLICATIONS USING THE CORRESPONDING TABLE - A database server provides a partitioned table with a corresponding locally partitioned index. When a request is made to load data into the table by an application, a table partition, along with a corresponding index partition, is created for the application. The corresponding index partition in marked as asynchronously maintained, allowing other index partitions to be used by the query optimizer in formulating query plans for other table partitions. Once the loading of data is complete, a synchronization operation is called with the result of conforming the data in the asynchronously maintained index partition with its corresponding table in which the data was loaded. Once the data in the corresponding table partition and the data in the asynchronously maintained index partition are synchronized, the asynchronously maintained index partition is marked as synchronously maintained. | 09-16-2010 |
20100306219 | Cache-Based Predicate Handling For Queries On XML Data Using Uncorrelated Path-Based Row Sources - The approaches described herein provide an efficient way to process certain kinds of queries that retrieve XML data stored in an object-relational database. An XML query may include a predicate condition that joins two row sources. One or both of the row sources required for predicate evaluation may be path-based; that is, consume and produce rows of XMLType data. Such a path-based row source may be modified to use the predicate condition to filter the rows it generates so that only rows satisfying the predicate condition need to be further processed. A small cache structure introduced into the path-based row source may be used to optimize the evaluation of the predicate row. Once populated with row data, the cache structure may be reorganized to optimize the performance of predicate evaluation. | 12-02-2010 |
20110066654 | OPERATIONALLY COMPLETE HIERARCHICAL REPOSITORY IN A RELATIONAL DATABASE - A modular repository is described, where operational features may be implemented without the need to scan every resource included in the modular repository. A modular repository includes a dedicated set of database objects containing all information needed to access the resources in the repository. For example, the database objects of a modular repository may include those user identifier mappings and ACL mappings, etc., to which metadata in the modular repository refers. A database system may also include a mechanism through which a modular repository may be mounted under a subdirectory of a common directory in the database system. The resources of a modular repository that are mounted under the common directory may be accessed through the common directory. Further, a client may query the resources of any modular repository mounted under the common directory by making the federated repository, represented by the common directory, the context of the query. | 03-17-2011 |
20110179089 | TECHNIQUES FOR EFFICIENT AND SCALABLE PROCESSING OF COMPLEX SETS OF XML SCHEMAS - Techniques are described herein for efficient and scalable processing of complex sets of XML schemas. The techniques described herein provide for reducing duplication of schema elements in volatile memory by building an XML schema in-memory model that stores repeating schema elements in in-memory data structures that are separate from in-memory data structures that store the parent schema elements which logically include or otherwise refer to the repeating schema elements. The techniques described herein also provide for faster generation of an in-memory model of an XML schema by pre-loading, in data structures on persistent storage, of schema elements from dependent XML schemas that are referenced and/or incorporated by the XML schema. The techniques described herein also provide for efficient processing of inter-dependent XML schemas by tracking all unresolved schema elements from dependent XML schemas and freeing the portions of volatile memory, which are used to process schema elements from the dependent XML schemas, as soon as the dependent schema elements being processed are stored in data structures on persistent storage. | 07-21-2011 |
20110295817 | Technique For Compressing XML Indexes - A method and apparatus for XXX is provided. | 12-01-2011 |
20120066271 | Operationally Complete Hierarchical Repository In A Relational Database - A modular repository is described, where operational features may be implemented without the need to scan every resource included in the modular repository. A modular repository includes a dedicated set of database objects containing all information needed to access the resources in the repository. For example, the database objects of a modular repository may include those user identifier mappings and ACL mappings, etc., to which metadata in the modular repository refers. A database system may also include a mechanism through which a modular repository may be mounted under a subdirectory of a common directory in the database system. The resources of a modular repository that are mounted under the common directory may be accessed through the common directory. Further, a client may query the resources of any modular repository mounted under the common directory by making the federated repository, represented by the common directory, the context of the query. | 03-15-2012 |