Abstract: Techniques for replicating data in database systems are described. In an example embodiment, a set of changes is received at a destination database, where the set of changes has been applied at a source database and is being replicated from the source database to the destination database. The set of changes is analyzed and it is determined that the set of changes includes two or more of: a subset of row-level changes, a subset of statement-level changes, and a subset of procedure-level changes. A set of dependencies is determined at least between the changes that are included in the subsets of changes. The changes, in the subsets of changes, are assigned to two or more processing elements. The set of changes is applied to the destination database by executing the two or more processing elements in parallel to each other and based on the set of dependencies.

Abstract: Techniques for replicating data in database systems are described. In an example embodiment, a set of changes is received at a destination database, where the set of changes has been applied at a source database and is being replicated from the source database to the destination database. The set of changes is analyzed and it is determined that the set of changes includes two or more of: a subset of row-level changes, a subset of statement-level changes, and a subset of procedure-level changes. A set of dependencies is determined at least between the changes that are included in the subsets of changes. The changes, in the subsets of changes, are assigned to two or more processing elements. The set of changes is applied to the destination database by executing the two or more processing elements in parallel to each other and based on the set of dependencies.

Abstract: An approach for reducing transport of messages between nodes of a multi-node system is presented wherein a message queue is associated with a queue service, and based on which node the message queue resides, one of the nodes is registered as hosting the associated queue service. In response to a client attempting to connect and requesting a particular queue service, the client is caused to connect to the node on which the queue service resides.

Abstract: Approaches described herein may be used for provisioning of databases that requires a bulk transfer of data within a distributed computing environment, such as a grid. The approaches do not require the manual intervention of a DBA to, for example, transfer a tablespace between the file systems of operating systems. Instead, the tablespaces may be provisioned automatically and dynamically by a grid computing system whenever it determines the need to dynamically provision a database. In addition, as copies of tablespaces are provisioned, synchronization mechanisms can also be automatically provisioned to keep the tablespaces and their copies in sync.

Abstract: Systems and methods for providing a one-step API that executes a series of atomic transactions in a database system. In one implementation, each atomic transaction is associated with a forward block of code that effects changes, an undo block of code that reverses the changes made by the forward block, and a state block of code that mimics successful execution of the forward block by setting internal states. In the event of a failure, the forward blocks, undo blocks, and state blocks can be used to roll forward or roll back changes as a whole. In one implementation, a one-step API for replicating data in a database is provided.

Abstract: Systems and methods for providing a one-step API that executes a series of atomic transactions in a database system. In one implementation, each atomic transaction is associated with a forward block of code that effects changes, an undo block of code that reverses the changes made by the forward block, and a state block of code that mimics successful execution of the forward block by setting internal states. In the event of a failure, the forward blocks, undo blocks, and state blocks can be used to roll forward or roll back changes as a whole. In one implementation, a one-step API for replicating data in a database is provided.

Abstract: Described herein are various approaches that allow rules to be used to specify actions, that alleviate the complexity and burden of developing and maintaining rules in a rules-based messaging system, and that provide more efficient ways of evaluating rules. The approaches allow rules to specify user-defined transformation functions for transforming messages, to specify when and how to perform row migration, and to specify other types of actions. Rules are grouped into rule sets. Several types of rule sets, referred to as positive and negative rule sets, allow users to use rules that are less complex to develop and maintain. Rule sets are evaluated more efficiently by attempting to evaluate the rule set with less information than is needed to evaluate all the rules in the rule set. Also, the results of rules evaluations that are based on a set of values are cached for later retrieval.

Abstract: Approaches described herein may be used for provisioning of databases that requires a bulk transfer of data within a distributed computing environment, such as a grid. The approaches do not require the manual intervention of a DBA to, for example, transfer a tablespace between the file systems of operating systems. Instead, the tablespaces may be provisioned automatically and dynamically by a grid computing system whenever it determines the need to dynamically provision a database. In addition, as copies of tablespaces are provisioned, synchronization mechanisms can also be automatically provisioned to keep the tablespaces and their copies in sync.

Abstract: Approaches described herein may be used for provisioning of databases that requires a bulk transfer of data within a distributed computing environment, such as a grid. The approaches do not require the manual intervention of a DBA to, for example, transfer a tablespace between the file systems of operating systems. Instead, the tablespaces may be provisioned automatically and dynamically by a grid computing system whenever it determines the need to dynamically provision a database. In addition, as copies of tablespaces are provisioned, synchronization mechanisms can also be automatically provisioned to keep the tablespaces and their copies in sync.

Abstract: An approach is provided to automatically resolve conflict between instantiation and ongoing data replication operations. In an embodiment, incremental change records that describe one or more database operations are received at a sink entity. Here, all of the one or more database operations have occurred in a second database after a particular time. A first database operation in the one or more database operations to a particular row in the first database is applied. When a conflict with a second database operation that operates on the particular row is detected, one or more compensating actions, which may, but are not limited to, be a different database operation and/or an operation that creates a conflict log entry, may be performed. Here, the second database operation has occurred in the second database prior to the particular time. When the second database operation is to be performed, an appropriate operation may be performed.

Abstract: Described herein are various approaches that allow rules to be used to specify actions, that alleviate the complexity and burden of developing and maintaining rules in a rules-based messaging system, and that provide more efficient ways of evaluating rules. The approaches allow rules to specify user-defined transformation functions for transforming messages, to specify when and how to perform row migration, and to specify other types of actions. Rules are grouped into rule sets. Several types of rule sets, referred to as positive and negative rule sets, allow users to use rules that are less complex to develop and maintain. Rule sets are evaluated more efficiently by attempting to evaluate the rule set with less information than is needed to evaluate all the rules in the rule set. Also, the results of rules evaluations that are based on a set of values are cached for later retrieval.

Abstract: To export source tablespaces, an auxiliary database system is created and started with a minimum configuration. Copies of versions of the source tablespaces are restored from database backups to the auxiliary database system. A copy of a version of a tablespace is referred to herein as a tablespace instance. The tablespace instances restored from database backups are recovered to a particular point-in-time. A script is then generated. The script can be executed by a database server of the destination database to import the tablespace instances.

Abstract: In some messaging system architectures, messages can cycle back to the originator of a message, who may then propagate the message, causing the cycle to be repeated. Described herein are techniques that use rules and fields in a redo log, to manage message flows such that undesired cycles are prevented. The techniques may be used in messaging systems that have various topologies.

Abstract: An approach is provided to automatically resolve conflict between instantiation and ongoing data replication operations. In an embodiment, incremental change records that describe one or more database operations are received at a sink entity. Here, all of the one or more database operations have occurred in a second database after a particular time. A first database operation in the one or more database operations to a particular row in the first database is applied. When a conflict with a second database operation that operates on the particular row is detected, one or more compensating actions, which may, but are not limited to, be a different database operation and/or an operation that creates a conflict log entry, may be performed. Here, the second database operation has occurred in the second database prior to the particular time. When the second database operation is to be performed, an appropriate operation may be performed.

Abstract: An extensible rules engine that uses database technology provides a rules evaluation service for applications external to the database server or database management system. Applications are able to utilize the rules engine to provide alternative behaviors based on information against which specified conditions are evaluated. A framework is provided for specifying data definitions that can be referenced by user-defined rules, through creation and use of an evaluation context. Application-specific data types can be defined by specifying data tables and/or variables that can be referenced by rules created for evaluation against data that is associated with the evaluation context. The data against which rules are evaluated can be provided as an in-memory object. A security model is provided in which the privilege to create rules according to a particular evaluation context is controlled by one privilege, whereas the privilege to access underlying tables or variables is controlled by another privilege.

Abstract: An approach for reducing transport of messages between nodes of a multi-node system is presented wherein a message queue is associated with a queue service, and based on which node the message queue resides, one of the nodes is registered as hosting the associated queue service. In response to a client attempting to connect and requesting a particular queue service, the client is caused to connect to the node on which the queue service resides.

Abstract: Data consistency in the context of information sharing requires maintenance of dependencies among information being shared. Transactional dependency ordering is implemented in a database system message queue, by associating a unique system commit time with each transactional message group. Read consistency is implemented in such a queue by allowing only messages with a fully determined order to be visible. A fully determined order is implemented through use of a high watermark, which guarantees that future transactions, for which messages are entering the queue, have commit times that are greater than the current high watermark. Therefore, only messages below the current high watermark are visible and can be dequeued, with no chance of other new messages enqueuing below the current high watermark.

Abstract: Systems and methods for providing a one-step API that executes a series of atomic transactions in a database system. In one implementation, each atomic transaction is associated with a forward block of code that effects changes, an undo block of code that reverses the changes made by the forward block, and a state block of code that mimics successful execution of the forward block by setting internal states. In the event of a failure, the forward blocks, undo blocks, and state blocks can be used to roll forward or roll back changes as a whole. In one implementation, a one-step API for replicating data in a database is provided.

Abstract: To export source tablespaces, an auxiliary database system is created and started with a minimum configuration. Copies of versions of the source tablespaces are restored from database backups to the auxiliary database system. A copy of a version of a tablespace is referred to herein as a tablespace instance. The tablespace instances restored from database backups are recovered to a particular point-in-time. A script is then generated. The script can be executed by a database server of the destination database to import the tablespace instances.