Abstract: Techniques are disclosed for disconnected operation in a distributed database system. In an embodiment, the distributed database system implements a disconnected mode of operation allowing isolated regions of database nodes to provisionally commit transactions, with the global requirements of those transactions later satisfied by a transparent healing process after network connectivity is reestablished between the regions. The healing process, in turn, enables the distributed database system to construct a consistent global state of the database that accounts for the transactions provisionally-committed in each isolated region during the disconnected mode. Once the healing process completes, database clients “see” a healed version of the database that simulates or otherwise closely approximates a state of the database had the distributed database system performed the transactions during a normal, fully-connected, mode of operation.

Abstract: Techniques are disclosed for implementing a unified partitioning scheme within distributed database systems to allow a table to be horizontally partitioned and those partitions stored on and serviced by a storage group. A storage group is a subset of storage manager (SM) nodes, and each SM node is configured to persist database data in durable storage. The distributed database system assigns each storage group to a subset of SM nodes. The distributed database system can address each storage group using a symbolic mapping that allows transactions to identify a particular storage group, and to direct read and write operations to a subset of SM nodes servicing that storage group. An administrator can update this mapping on-the-fly to cause the distributed database system to dynamically adjust an implemented partitioning scheme without necessarily interrupting on-going database operations.

Abstract: A data processing network includes a database management for a plurality of databases serviced by a server comprising a plurality of data processors. Each server data processor includes a copy of the database management system and a monitor for measuring and analyzing various parameters for each server data processor and each included database and performing various methods transparently to a user. For example, when a parameter or combination thereof indicates that a database in one data processor is inactive or requires additional resources, that database is set to an inactive state or is transferred to another data processor with greater resources, respectively. An inactive database is recalled upon receipt of a request for access to that database. A database in a data processor of greater resources can be returned to a server data processor or another data processor with fewer resources. These operations are transparent to database users and independent of user or administrator intervention.

Abstract: A Resource Description Framework engine is disclosed for performing transactional RDF-based operations against a distributed database. The RDFE manages a local memory cache that stores active portions of the database, and can synchronize those active portions using a transactionally-coherent distributed cache across all database nodes. During RDF reads, the RDFE can identify a triple-store table affected by a given RDF transaction, and can traverse the index objects for that table to locate triple values that satisfy a given RDF query, without intervening SQL operations. The RDFE can also perform SQL transactions or low-level write operations to update triples in triple-store tables. Thus the RDFE can update corresponding index objects contemporaneous with the insertion of RDF triples, with those updates replicated to all database nodes.

Abstract: Techniques are disclosed for implementing a unified partitioning scheme within distributed database systems to allow a table to be horizontally partitioned and those partitions stored on and serviced by a storage group. A storage group is a subset of storage manager (SM) nodes, and each SM node is configured to persist database data in durable storage. The distributed database system assigns each storage group to a subset of SM nodes. The distributed database system can address each storage group using a symbolic mapping that allows transactions to identify a particular storage group, and to direct read and write operations to a subset of SM nodes servicing that storage group. An administrator can update this mapping on-the-fly to cause the distributed database system to dynamically adjust an implemented partitioning scheme without necessarily interrupting on-going database operations.

Abstract: Techniques are disclosed for disconnected operation in a distributed database system. In an embodiment, the distributed database system implements a disconnected mode of operation allowing isolated regions of database nodes to provisionally commit transactions, with the global requirements of those transactions later satisfied by a transparent healing process after network connectivity is reestablished between the regions. The healing process, in turn, enables the distributed database system to construct a consistent global state of the database that accounts for the transactions provisionally-committed in each isolated region during the disconnected mode. Once the healing process completes, database clients “see” a healed version of the database that simulates or otherwise closely approximates a state of the database had the distributed database system performed the transactions during a normal, fully-connected, mode of operation.

Abstract: A node failure detector for use in a distributed database that is accessed through a plurality of interconnected transactional and archival nodes. Each node is selected as an informer node that tests communications with each other node. Each informer node generates a list of suspicious nodes that is resident in one node designated as a leader node. The leader node analyzes the data from all of the informer nodes to designate each node that should be designated for removal with appropriate failover procedures.

Abstract: Techniques are disclosed for backup and restore in a distributed database utilizing consistent database snapshots. In particular, a distributed database system configured in accordance with an embodiment of the present disclosure includes a plurality of interconnected database nodes that collectively define a database having no single point of failure and that can be “viewed” by a SQL client as a single, logical database. In the course of executing such transactions, the distributed database system enables clients to declare snapshots that, when the transaction is committed, cause the distributed database system to logically freeze a consistent and complete copy of the state of the database at the point in time the transaction completed. Such snapshots enable clients to execute so-called “point-in-time” queries against those past states to return a result set that is essentially a reconstructed version of the database “as of” a particular point in time.

Abstract: A data processing network includes a database management for a plurality of databases serviced by a server comprising a plurality of data processors. Each server data processor includes a copy of the database management system and a monitor for measuring and analyzing various parameters for each server data processor and each included database and performing various methods transparently to a user. For example, when a parameter or combination thereof indicates that a database in one data processor is inactive or requires additional resources, that database is set to an inactive state or is transferred to another data processor with greater resources, respectively. An inactive database is recalled upon receipt of a request for access to that database. A database in a data processor of greater resources can be returned to a server data processor or another data processor with fewer resources. These operations are transparent to database users and independent of user or administrator intervention.

Abstract: A multi-user, elastic, on-demand, distributed relational database management system. The database is fragmented into distributed objects called atoms. Any change to a copy of an atom at one location is replicated to all other locations containing a copy of that atom. Transactional managers operate to satisfy the properties of atomicity, consistency, isolation and durability.

Abstract: A multi-user, elastic, on-demand, distributed relational database management system. The database is fragmented into distributed objects called atoms. Any change to a copy of an atom at one location is replicated to all other locations containing a copy of that atom. Transactional managers operate to satisfy the properties of atomicity, consistency, isolation and durability.

Abstract: A multi-user, elastic, on-demand, distributed relational database management system. The database is fragmented into distributed objects called atoms. Any change to a copy of an atom at one location is replicated to all other locations containing a copy of that atom. Transactional managers operate to satisfy the properties of atomicity, consistency, isolation and durability.

Abstract: A multi-user, elastic, on-demand, distributed relational database management system. The database is fragmented into distributed objects called atoms. Any change to a copy of an atom at one location is replicated to all other locations containing a copy of that atom. Transactional managers operate to satisfy the properties of atomicity, consistency, isolation and durability.