Abstract: Techniques are described for preserving the inflight sessions failing over from a primary database to the replicated logical database of the primary database. In an implementation, prior to failover, when the primary database server receives a commit for a transaction, the process stores a commit indication that the transaction has been committed by performing a corresponding SQL command. The commit indication is replicated to the logical replica database by virtue of the replication of the SQL command and its execution on the logical replica database. Accordingly, the standby database server in the failover session may successfully request for the outcome of the transaction. Techniques are also described for the client-side LOB references to be preserved when failing over to the logical replica database, for AS OF queries preserved, and for versioning of checksums, signatures and structures across logical replicas.

Abstract: Disclosed is a method, a computer program product, and a computer system for implementing automatic connection load balancing of database connections between instances of a cluster. Load imbalances are detected globally in the cluster, and can be corrected autonomously by the local instances. The local controller/orchestrator detects the imbalance, computes a target for the instance, and makes any necessary adjustments on the instance, where a server marks the connections to redistribute, and then implements draining and/or planned failover to move sessions.

Abstract: Disclosed is a method, a computer program product, and a computer system for implementing automatic connection load balancing of database connections between instances of a cluster. Load imbalances are detected globally in the cluster, and can be corrected autonomously by the local instances. The local controller/orchestrator detects the imbalance, computes a target for the instance, and makes any necessary adjustments on the instance, where a server marks the connections to redistribute, and then implements draining and/or planned failover to move sessions.

Abstract: A method and apparatus is provided for dynamically generating data to dataset mappings and dataset to logical instance mappings and distributing these mappings to subscribers for the purpose of routing work. An advisory engine updates the mappings of data to data sets based at least in part on changing demands and patterns of access to data, and updates the mappings of datasets to logical instances based at least in part on anticipated capacity and change in conditions of the database servers. The subscribers receive and store the mapping information that maps the data to dataset identifiers, and dataset identifiers to logical database instances. The subscribers may also receive information that describes the current availability conditions of database instances, which are used to override the mapping of logical database instances to physical database instances. Subscribers may use the data to dataset mapping to map data identified from in an incoming database request to a dataset.

Abstract: Systems and methods are provided for supporting transaction recovery based on inline delegation of transaction logs to a database. The system can retrieve transaction recovery information of a transaction from a persistence store, wherein the transaction recovery information is persisted on a resource manager that is associated with the persistence store during a prepare phase. Furthermore, the system can retrieve one or more in-doubt transactions from one or more participating resource managers of the transaction. Then, the system can determine whether to commit or roll back the one or more in-doubt transactions by matching the one or more in-doubt transactions to the transaction recovery information.

Abstract: A method and apparatus is provided for dynamically generating data to dataset mappings and dataset to logical instance mappings and distributing these mappings to subscribers for the purpose of routing work. An advisory engine updates the mappings of data to data sets based at least in part on changing demands and patterns of access to data, and updates the mappings of datasets to logical instances based at least in part on anticipated capacity and change in conditions of the database servers. The subscribers receive and store the mapping information that maps the data to dataset identifiers, and dataset identifiers to logical database instances. The subscribers may also receive information that describes the current availability conditions of database instances, which are used to override the mapping of logical database instances to physical database instances. Subscribers may use the data to dataset mapping to map data identified from in an incoming database request to a dataset.

Abstract: A method and apparatus is provided for dynamically generating data to dataset mappings and dataset to logical instance mappings and distributing these mappings to subscribers for the purpose of routing work. An advisory engine updates the mappings of data to data sets based at least in part on changing demands and patterns of access to data, and updates the mappings of datasets to logical instances based at least in part on anticipated capacity and change in conditions of the database servers. The subscribers receive and store the mapping information that maps the data to dataset identifiers, and dataset identifiers to logical database instances. The subscribers may also receive information that describes the current availability conditions of database instances, which are used to override the mapping of logical database instances to physical database instances. Subscribers may use the data to dataset mapping to map data identified from in an incoming database request to a dataset.

Abstract: Systems and methods are provided for supporting transaction recovery based on inline delegation of transaction logs to a database. The system can retrieve transaction recovery information of a transaction from a persistence store, wherein the transaction recovery information is persisted on a resource manager that is associated with the persistence store during a prepare phase. Furthermore, the system can retrieve one or more in-doubt transactions from one or more participating resource managers of the transaction. Then, the system can determine whether to commit or roll back the one or more in-doubt transactions by matching the one or more in-doubt transactions to the transaction recovery information.

Abstract: A method and apparatus is provided for dynamically generating data to dataset mappings and dataset to logical instance mappings and distributing these mappings to subscribers for the purpose of routing work. An advisory engine updates the mappings of data to data sets based at least in part on changing demands and patterns of access to data, and updates the mappings of datasets to logical instances based at least in part on anticipated capacity and change in conditions of the database servers. The subscribers receive and store the mapping information that maps the data to dataset identifiers, and dataset identifiers to logical database instances. The subscribers may also receive information that describes the current availability conditions of database instances, which are used to override the mapping of logical database instances to physical database instances. Subscribers may use the data to dataset mapping to map data identified from in an incoming database request to a dataset.

Abstract: Various embodiments of the invention provide solutions to allow more sophisticated management of the relationship between a database and its clients (which can be, inter alia, end users, business applications, etc.). Merely by way of example, some embodiments can facilitate the management of work requests in a database, as well as the management of the quality-of-service in a database system. In some embodiments, an identification handle may be assigned to a database work request. A database management application can use the identification handle to identify the work request, as well, perhaps, as any related work requests. The identification handle may also identify the database (and/or an instance thereof) and/or a clustered database node, and the identification handle may be transmitted to a mid-tier application, e.g., to notify the mid-tier about the processing of the work request, changes in quality-of service, server availability, etc.

Abstract: A composite resource is established that includes a plurality of members. Each of the members is capable of providing a comparable service. A coordinator monitors a state of each member of the composite resource. A component requests the service from the coordinator. The coordinator arranges for the service to be provided to the component by a particular member of the composite resource. When the particular member ceases to be active, the service is automatically provided to the component by another member in the composite resource. A state of the composite resource is maintained independently of the state of each member in the composite resource.

Abstract: A composite resource is established that includes a plurality of members. Each of the members is capable of providing a comparable service. A coordinator monitors a state of each member of the composite resource. A component requests the service from the coordinator. The coordinator arranges for the service to be provided to the component by a particular member of the composite resource. When the particular member ceases to be active, the service is automatically provided to the component by another member in the composite resource. A state of the composite resource is maintained independently of the state of each member in the composite resource.

Abstract: Events of interest are detected in order to manage a high availability framework. In a framework in which a plurality of components are executing, the components are periodically polled to detect occurrence of the event of interest. A monitor is also established for one or more of the components. After the first component causes the event of interest to occur, the monitor communicating the event of interest to the framework without waiting for the framework to poll the first component.

Abstract: Events of interest are detected in order to manage a high availability framework. In a framework in which a plurality of components are executing, the components are periodically polled to detect occurrence of the event of interest. A monitor is also established for one or more of the components. After the first component causes the event of interest to occur, the monitor communicating the event of interest to the framework without waiting for the framework to poll the first component.

Abstract: A composite resource is established that includes a plurality of members. Each of the members is capable of providing a comparable service. A coordinator monitors a state of each member of the composite resource. A component requests the service from the coordinator. The coordinator arranges for the service to be provided to the component by a particular member of the composite resource. When the particular member ceases to be active, the service is automatically provided to the component by another member in the composite resource. A state of the composite resource is maintained independently of the state of each member in the composite resource.

Abstract: A composite resource is established that includes a plurality of members. Each of the members is capable of providing a comparable service. A coordinator monitors a state of each member of the composite resource. A component requests the service from the coordinator. The coordinator arranges for the service to be provided to the component by a particular member of the composite resource. When the particular member ceases to be active, the service is automatically provided to the component by another member in the composite resource. A state of the composite resource is maintained independently of the state of each member in the composite resource.