Abstract: A method and system to define a plurality of benchmark component types, each of the benchmark component types being a meta model defining the benchmark component type; generate instances of the plurality of benchmark component types; define parameters associated with the plurality of benchmark component types; and combine one or more of the instances of the plurality of benchmark component types and the defined parameters associated with the benchmark component types being combined.

Abstract: A method for updating a block on disk is provided. The method involves one or more clients committing log records to queues corresponding to blocks. The method further involves checkpointing, which includes obtaining a flushing lock on the queue by a client, receiving log records from the queue, applying the log records to a block on disk, and deleting the log records from the queue. A block on disk may be updated by first applying the log records from a queue to a locally cached version of the block corresponding to the queue. The locally cached version may then be stored on the disk replacing the original block on disk or being stored as a new version of the original block.

Abstract: Calculation of aggregated values in a history database table can be optimized using an approach in which an ordered history table is accessed. The ordered history table can include a sequential listing of commit identifiers associated with updates, insertions, and/or deletions to values in the database table. The ordered history table can be traversed in a single pass to calculate an aggregation function using an optimized algorithm. The optimized algorithm can enable calculation of an aggregated metric of the values based on a selected method for tracking invalidated values to their corresponding commit identifiers. The calculated metric is generated for a current version of the database table; and promoted.

Abstract: A system and method of performing snapshot isolation in distributed databases. Each node stores local snapshot information that enforces snapshot isolation for that node. The method includes partially processing a distributed transaction by a first node, receiving a global commit identifier from a coordinator, and continuing to process the distributed transaction, by the first node and a second node, in accordance with the global commit identifier.

Abstract: A method for storing and retrieving data in a storage node of a data store and storage node of a data store, storing in main-memory at least one segment of a relational table The storage node includes at least one computational core running at least one scan thread each dedicated to the scanning of one of the at least one segment. At least one scan thread uniquely, continuously and exhaustively scans the dedicated segment of the relational table. The storage node receives and processes batches of query and update operations for the at least one segment of the relational table. The query and update operations of a batch are re-indexed at beginning of each scan by the scan thread. Then, the indexed query and update operations of a batch are independently joined to data records of said segment that match with predicates of the indexed query and update operations.

Abstract: A method for updating a block on disk is provided. The method involves one or more clients committing log records to queues corresponding to blocks. The method further involves checkpointing, which includes obtaining a flushing lock on the queue by a client, receiving log records from the queue, applying the log records to a block on disk, and deleting the log records from the queue. A block on disk may be updated by first applying the log records from a queue to a locally cached version of the block corresponding to the queue. The locally cached version may then be stored on the disk replacing the original block on disk or being stored as a new version of the original block.

Abstract: A system and method for avoiding accessing a remote database twice, once during query execution and again to retrieve objects identified by the query, when an application requires objects on which to operate. During query plan generation in response to a request for database objects from an application, a query optimizer inserts cache operators into the candidate plans, and then a cost-benefit analysis is undertaken to identify the best plan. The best plan is then used to execute the query, with the cache operators causing objects identified during query execution to be cached locally to the requesting application as the query is being executed, thereby avoiding requiring the application to access the database after query execution.

Abstract: Systems and methods in accordance with the present invention provide for an implementation of the XQuery standard, and such an implementation will be referred to herein as an XQuery (XML Query language) implementation. An XQuery implementation can be based on a token stream representation, which allows large XML documents to be processed without having to first read the entire document. An XQuery implementation can also utilize a streaming XQuery engine. A set of algorithms and a set of rewrite rules can be used for the implementation. Given a query, a set of rules can be applied to that query to transform the query into another query. Some of these rules allow the resulting query to be streamable. In other words, a query that would otherwise require an XML document to be read into memory can now be transformed into a query that can work on an XML stream. The type system of the XQuery language can be based on XML Schema, and the basic types of XML Schema can have derived types.

Abstract: Systems and methods in accordance with the present invention provide for an implementation of the XQuery standard, and such an implementation will be referred to herein as an XQuery (XML Query language) implementation. An XQuery implementation can be based on a token stream representation, which allows large XML documents to be processed without having to first read the entire document. An XQuery implementation can also utilize a streaming XQuery engine. A set of algorithms and a set of rewrite rules can be used for the implementation. Given a query, a set of rules can be applied to that query to transform the query into another query. Some of these rules allow the resulting query to be streamable. In other words, a query that would otherwise require an XML document to be read into memory can now be transformed into a query that can work on an XML stream. The type system of the XQuery language can be based on XML Schema, and the basic types of XML Schema can have derived types.