Abstract: In transferring data from/to a database server, the size of a network buffer used by a network layer is dynamically adjusted according to the call type and expected size of data to be transferred for the call. Due to such use of appropriate buffer size, throughput performance of the transfer may be enhanced.

Abstract: The present invention is directed to a method and mechanism for reducing the expense of data transmissions between a client and a server. According to an aspect of data prefetching is utilized to predictably retrieve information between the client and server. Another aspect pertains to data redundancy management for reducing the expense of transmitting and storing redundant data between the client and server. Another aspect relates to moved data structures for tracking and managing data at a client in conjunction with data redundancy management.

Abstract: The present invention is directed to a method and mechanism for reducing the expense of data transmissions between a client and a server. According to an aspect of data prefetching is utilized to predictably retrieve information between the client and server. Another aspect pertains to data redundancy management for reducing the expense of transmitting and storing redundant data between the client and server. Another aspect relates to moved data structures for tracking and managing data at a client in conjunction with data redundancy management.

Abstract: A system, method, computer program and system for suspending a result set and continuing from a suspended result set for a cursor is disclosed. The rows from a row source corresponding to the cursor result set are suspended into storage so that when a fetch is requested the data can be sent (continued) from the suspended storage and does not depend on the original cursor row source or session to be available.

Abstract: A system, method, computer program and system for suspending a result set and continuing from a suspended result set for a scrollable cursor is disclosed. The rows from a row source corresponding to the scrollable cursor result set are suspended into storage so that when a fetch is requested the data can be sent (continued) from the suspended storage and does not depend on the original scrollable cursor row source or session to be available.

Abstract: A system, method, computer program and system for suspending a result set and continuing from a suspended result set for transparent session migration is disclosed. The rows from a row source are suspended into storage, so that after session migration, the client fetches can transparently continue from the suspended result set.

Abstract: An approach migrates database sessions from a database server on which performance and resource availability requirements are not being met to another database server. Because workload is removed from the database server not meeting these requirements, improved performance there is promoted. Furthermore, the approach switches the users in a way that attempts to keep performance and resource availability levels at the database server receiving the database sessions within goals for performance and resource availability.

Abstract: Approaches are used for efficiently and effectively managing the dynamic allocation of resources of multi-node database systems between services provided by the multi-node database server. A service is a category of work that is hosted on the database server. The approaches manage allocation of resources at different levels. For services that use a particular database, the performance realized by the services is monitored. Resources assigned to the database are allocated between these services to ensure performance goals for each are met. Resources assigned to a cluster of nodes are allocated between the databases to ensure that performance goals for all the services that use the databases are met. Resources assigned to a farm of clusters are assigned amongst clusters based on service level agreements and back-end policies. The approach uses a hierarchy of directors to manage resources at the different levels.

Abstract: An approach provides for recovery of message driven directors responsible for dynamically allocating resources within a multi-node database system. The receipt of a message, the action taken in response to it, and other messages sent in furtherance of the action, are performed within a single transaction. In this way, the messages and other data are left in a state consistent with the message and action taken in response being fully processed or not processed at all. A standby director, stepping in for a crashed director, inherits a state consistent with where a crashed director last successfully completed an action. The approach insulates directors from the special perils of performing high latency actions by delegating the performance of such actions to a job, (i.e. another process).

Abstract: Techniques allow a client to be switched from a session on a server to another session on another server in a way that is a transparent to the application for which the initial session was established. Thus, under transparent session migration, a client is switched between sessions without executing application instructions tailored to accomplish the migration. Instead, a client-side interface component, through which the application interacts with the server, handles details of migration, modifying the internal state of the client-side interface component to effect the same. Legacy applications do not have to be modified in order to institute techniques described herein.

Abstract: Direct memory accessed is used to perform database operations between two or more machines. A first segment of memory is allocated for a second machine, where at least one of the first machine and second machine is a database server. During performance of a database operation that involves the transfer of data from the second machine to the first machine, data in the first segment of memory is buffered in response to the second machine writing the data to a second segment of memory on the second machine.

Abstract: One embodiment of the present invention provides a system that modifies a function defined within an application programming interface (API) so that the function includes additional code. The system receives an additional code module to be integrated into the function within the API. The system also receives a command to integrate the additional code module into the function. This command is received through a pre-defined function within the API for integrating additional code into functions within the API. In response to the command, the system links the additional code into the function so that the additional code module is executed when the function is called. In one embodiment of the present invention, linking the additional code module into the function involves linking the additional code module as an entry function that is executed at the beginning of the function.

Abstract: A method and apparatus can improve the performance of a server and clients by storing commands sent to the server until a command is received that fills the capacity of the apparatus to store the commands or that will cause the server to provide information beyond acknowledgment of or completion of the command. The commands are then set to the server software for execution. The server then processes as a group the commands stored, returning a single response, and eliminating the overhead that could have been incurred in providing multiple responses or processing the commands separately.

Abstract: A method and apparatus are provided for performing an array DML operation. During the performance of the operation on a data item in the array, and if an error occurs, then error information is stored and the array operation continues by performing the operation on the next data item in the array. The error is used to create update input data for the DML operation, and the update input data can be supplied during run-time of the program.

Abstract: A method and apparatus allows a client or other device separate from a server to retrieve from the server more data than is requested by an application program on the client. The additional data is maintained by the client or other device and provided to the application program in response to a subsequent request, reducing the number of times data is requested from the server, and also the processing and overhead required by the server to supply the data. If the server releases memory pointing to the data on the server at the time or after all data specified by the application program has been retrieved, because the data is potentially retrieved from the server in amounts larger than requested by the application program, the server may release memory pointing to the data on the server sooner than it would by processing requests for the data from the application program alone.

Abstract: A method and apparatus allows clients to share ports on a server. The server can maintain more sessions than server ports. When a client sends a command directed to the server, a resource manager inserted between the clients and the server intercepts the command and directs the server to select the session associated with a client prior to or at the same time that the resource manager forwards the intercepted command to the server. Responses from the server are forwarded by the resource manager to the client that sent the command to which the response relates. The resource manager may be coupled to multiple clients, and one or more ports of one or more servers.

Abstract: A method and apparatus for is provided for efficiently transmitting multiple rows of data to a client station. The client station generates a query that is transmitted to a remotely located server, which in turn generates a query result. The server transmits the first row of data from the query result to the client. The remaining rows of data are transmitted by first calculating the difference between successive rows of data. Next, the server sends only the unique rows resulting from the calculated row difference to the client. The server also send an indication of the number of non-repeated value columns detected in order to allow reconstruction of the query result by the client station.

Abstract: A method and apparatus allows clients to share ports on a server. The server can maintain more sessions than server ports. When a client sends a command directed to the server, a resource manager inserted between the clients and the server intercepts the command and directs the server to select the session associated with a client prior to or at the same time that the resource manager forwards the intercepted command to the server. Responses from the server are forwarded by the resource manager to the client that sent the command to which the response relates. The resource manager may be coupled to multiple clients, and one or more ports of one or more servers.