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: A system and method for allocating join processing between and RDBMS and an assisting cluster. In one embodiment, the method estimates a cost of performing the join completely in the RDBMS and the cost of performing the join with the assistance of a cluster coupled to the RDBMS. The cost of performing the join with the assistance of the cluster includes estimating a cost of a broadcast join or a partition join depending on the sizes of the tables. Additional costs are incurred when there is a blocking operation, which prevents the cluster from being able to process portions of the join. The RDBMS also maintains transactional consistency when the cluster performs some or all of the join processing.

Abstract: A system and method for performing a query operation on a pair of relations in a database system coupled to a heterogeneous system (HS) is disclosed. Assuming that that pair of relations is partitioned and already loaded into the HS, the database system receives a query on the pair of relations and based on the type of query operation computes the cost of performing the query operation on the database alone or the costs of performing the query operation with the assistance of the HS, each of the costs corresponding to a particular algorithm. If the costs indicate that the HS improves the performance of the query operation, then the HS computes portions of the operation, and returns the results back to the database system. If any parts of the relation are out of sync with the database system, the database system performs operations to maintain transactional consistency.

Abstract: A system and method for processing a group and aggregate query on a relation are disclosed. A database system determines whether assistance of a heterogeneous system (HS) of compute nodes is beneficial in performing the query. Assuming that the relation has been partitioned and loaded into the HS, the database system determines, in a compile phase, whether the HS has the functional capabilities to assist, and whether the cost and benefit favor performing the operation with the assistance of the HS. If the cost and benefit favor using the assistance of the HS, then the system enters the execution phase. The database system starts, in the execution phase, an optimal number of parallel processes to produce and consume the results from the compute nodes of the HS. After any needed transaction consistency checks, the results of the query are returned by the database system.

Abstract: A system and method for allocating join processing between and RDBMS and an assisting cluster. In one embodiment, the method estimates a cost of performing the join completely in the RDBMS and the cost of performing the join with the assistance of a cluster coupled to the RDBMS. The cost of performing the join with the assistance of the cluster includes estimating a cost of a broadcast join or a partition join depending on the sizes of the tables. Additional costs are incurred when there is a blocking operation, which prevents the cluster from being able to process portions of the join. The RDBMS also maintains transactional consistency when the cluster performs some or all of the join processing.

Abstract: A system and method for improving performance of join operations is disclosed. The method in one embodiment includes building a graph of vertices and edges, which represent the tables and join conditions for a particular database schema. The method then traverses the graph to find a set of candidate join operations. The method further includes selecting from the set of subset of join operations that makes the best use of a given amount of memory, which means finding a collection of denormalizations which when residing in memory provide the most benefit and the least cost for the given amount of memory. The method then deploys the denormalizations so that current queries in a query processing system can use them instead of actually performing the joins.

Abstract: One embodiment of the present invention provides a system for efficiently evaluating a security policy. During operation, the system retrieves one or more roles associated with the user. Next, the system checks if a session-level cache exists for a set of Access Control Entries (ACEs) which is associated with the one or more roles. If this session-level cache exists, the system returns the set of ACEs from the session-level cache. Otherwise, the system generates the set of ACEs associated with the one or more roles from an Access Control List (ACL). During operation, the system can also update the one or more roles associated with the user and update the set of ACEs based on the updated one or more roles and the ACL. The system subsequently updates the session level cache with the updated set of ACEs and updated one or more roles.

Abstract: A two-level cache to facilitate resolving resource path expressions for a hierarchy of resources is described, which includes a system-wide shared cache and a session-level cache. The shared cache is organized as a hierarchy of hash tables that mirrors the structure of a repository hierarchy. A particular hash table in a shared cache includes information for the child resources of a particular resource. A database management system that manages a shared cache may control the amount of memory used by the cache by implementing a replacement policy for the cache based on one or more characteristics of the resources in the repository. The session-level cache is a single level cache in which information for target resources of resolved path expressions may be tracked. In the session-level cache, the resource information is associated with the entire path expression of the associated resource.

Abstract: A two-level cache to facilitate resolving resource path expressions for a hierarchy of resources is described, which includes a system-wide shared cache and a session-level cache. The shared cache is organized as a hierarchy of hash tables that mirrors the structure of a repository hierarchy. A particular hash table in a shared cache includes information for the child resources of a particular resource. A database management system that manages a shared cache may control the amount of memory used by the cache by implementing a replacement policy for the cache based on one or more characteristics of the resources in the repository. The session-level cache is a single level cache in which information for target resources of resolved path expressions may be tracked. In the session-level cache, the resource information is associated with the entire path expression of the associated resource.

Abstract: Techniques for implementing fast loading of binary XML into a binary XML database repository are provided. A client application reduces the processing burden on the repository by doing pre-processing of the binary XML data prior to loading.

Abstract: One embodiment of the present invention provides a system for efficiently evaluating a security policy. During operation, the system retrieves one or more roles associated with the user. Next, the system checks if a session-level cache exists for a set of Access Control Entries (ACEs) which is associated with the one or more roles. If this session-level cache exists, the system returns the set of ACEs from the session-level cache. Otherwise, the system generates the set of ACEs associated with the one or more roles from an Access Control List (ACL). During operation, the system can also update the one or more roles associated with the user and update the set of ACEs based on the updated one or more roles and the ACL. The system subsequently updates the session level cache with the updated set of ACEs and updated one or more roles.

Abstract: Techniques for implementing fast loading of binary XML into a binary XML database repository are provided. A client application reduces the processing burden on the repository by doing pre-processing of the binary XML data prior to loading.

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.