Abstract: Methods and apparatus, including computer program products, for maintaining a set of indexes in a database management system (DBMS) having at least one table. A current, stale or deferred status is defined for at least a part of the indexes, resulting in at least a part of a set of current, stale, or deferred indexes in the DBMS. Current indexes are maintained by refreshing a current index synchronously with a table change relating to the current index. Stale indexes are maintained by refreshing a stale index continuously and asynchronously to table modifications of tables relating to the stale index based on log information relating to the modifications. Deferred indexes are maintained by building a deferred index in response to a query to a table relating to the deferred index, thereby bringing the deferred index in accordance with the current query time status to the table relating to the deferred index.

Abstract: Embodiments relate to operating a data processing system. An aspect includes receiving a request for data storage by an application server, said request comprising restricted-access data. Another aspect includes processing the request in the first application server thereby extracting said restricted-access data from the request. Another aspect includes encrypting said restricted-access data with a cryptographic key associated with said privacy regime to a cipher representation. Another aspect includes defining a masking rule relative to the field designated for storage of the cipher representation, the masking rule defining a set of privacy regimes applicable to processing of the restricted-access data. Another aspect includes forwarding the cipher representation and the masking rule to the shared database by a database client.

Abstract: Dynamically switching between a plurality of execution paths to execute a function, such as a user-defined function. The plurality of execution paths include an execution path that uses caching and another execution path that uses inlining. A user-defined function is executed at least once using a first execution path. Then, for a later execution of the function, the execution path is automatically switched to a second execution path.

Abstract: Embodiments related to processing of restricted-access data. An aspect includes receiving a request for data from a user by a storage system infrastructure comprising a centralized database that stores non-restricted access data and a local system that stores restricted-access data associated with a first set of areas or entities and comprising a federated database for providing a federated view, wherein the requested data comprises restricted-access first data and non-restricted access second data. Another aspect includes based on an association of the user, routing, by a routing entity, the request to the local system. Another aspect includes receiving the request at the at least one federated database of the local system. Another aspect includes retrieving from the federated database the restricted-access first data and the non-restricted access second data.

Abstract: Embodiments relate to operating a data processing system. An aspect includes receiving a request for data storage by an application server, said request comprising restricted-access data. Another aspect includes processing the request in the first application server thereby extracting said restricted-access data from the request. Another aspect includes encrypting said restricted-access data with a cryptographic key associated with said privacy regime to a cipher representation. Another aspect includes defining a masking rule relative to the field designated for storage of the cipher representation, the masking rule defining a set of privacy regimes applicable to processing of the restricted-access data. Another aspect includes forwarding the cipher representation and the masking rule to the shared database by a database client.

Abstract: Operating a parallel database server system, where the database server system comprises at least two database servers and one data source. A client identifier is received from a client requesting services from one of said database servers. Information associated with said client is retrieved. The client is allocated to one of said database servers based on the retrieved information.

Abstract: Methods and Apparatus, including computer program products, for maintaining indexes in a database management system. The database management system includes a table having table entries and an index data structure having index data structure entries, the index data structure relating to the table. The index data structure is updated synchronously with an insertion of table entries. The index data structure is maintained unchanged when the table entries are deleted. It is verified by an index-scan on the index data structure that a valid criterion is fulfilled for index data structure entries, and those index data structure entries that pass the valid criterion from the index-scan are returned.

Abstract: According to one embodiment of the present invention, a method for identifying relevant database indexes is provided. According to one embodiment of the present invention, a method includes determining the importance of a particular database transaction and storing an index name related to the transaction along with an indicator of the importance. A database transaction is initiated and the importance indicator is received in an index advisor. The index advisor then makes an index recommendation based on the index importance.

Abstract: Methods and apparatus, including computer program products, for maintaining a set of indexes in a database management system (DBMS) having at least one table. A current, stale or deferred status is defined for at least a part of the indexes, resulting in at least a part of a set of current, stale, or deferred indexes in the DBMS. Current indexes are maintained by refreshing a current index synchronously with a table change relating to the current index. Stale indexes are maintained by refreshing a stale index continuously and asynchronously to table modifications of tables relating to the stale index based on log information relating to the modifications. Deferred indexes are maintained by building a deferred index in response to a query to a table relating to the deferred index, thereby bringing the deferred index in accordance with the current query time status to the table relating to the deferred index.

Abstract: Methods and Apparatus, including computer program products, for maintaining indexes in a database management system. The database management system includes a table having table entries and an index data structure having index data structure entries, the index data structure relating to the table. The index data structure is updated synchronously with an insertion of table entries. The index data structure is maintained unchanged when the table entries are deleted. It is verified by an index-scan on the index data structure that a valid criterion is fulfilled for index data structure entries, and those index data structure entries that pass the valid criterion from the index-scan are returned.

Abstract: Operating a parallel database server system, where the database server system comprises at least two database servers and one data source. A client identifier is received from a client requesting services from one of said database servers. Information associated with said client is retrieved. The client is allocated to one of said database servers based on the retrieved information.

Abstract: According to one embodiment of the present invention, a method for identifying relevant database indexes is provided. According to one embodiment of the present invention, a method includes determining the importance of a particular database transaction and storing an index name related to the transaction along with an indicator of the importance. A database transaction is initiated and the importance indicator is received in an index advisor. The index advisor then makes an index recommendation based on the index importance.

Abstract: A method of searching a data page in a table space of a database for inserting a data record to a first table, wherein the table space comprises space map pages and sets of data pages, wherein each space map page comprises information about the available storage space of one set of data pages, wherein each space map page and the corresponding set of data pages is further assigned to a table range for each table to which at least one data page in the set of data pages belongs to, wherein the database further comprises a clustering index for the first table in the database management system, wherein the database management system comprises a space usage information database, and wherein the space usage information database holds space usage information for each table range.

Abstract: Presented is a method to perform a query to retrieve data from a database that is part of a computer system comprising a Data-Base Management System (DBMS) with an optimizer. A Query Execution Plan (QEP) is generated for the query. The QEP is assessed by considering statistical values about previous executions of the query according to the QEP to decide whether to choose the QEP or to generate a new QEP. Furthermore, the statistical values on previous executions of the query are exploited during query optimization. The query is executed according to the chosen QEP. For optimizing the execution of future queries, statistical values about the execution of the query are collected during execution.

Abstract: A method of searching a data page in a table space of a database for inserting a data record to a first table, wherein the table space comprises space map pages and sets of data pages, wherein each space map page comprises information about the available storage space of one set of data pages, wherein each space map page and the corresponding set of data pages is further assigned to a table range for each table to which at least one data page in the set of data pages belongs to, wherein the database further comprises a clustering index for the first table in the database management system, wherein the database management system comprises a space usage information database, and wherein the space usage information database holds space usage information for each table range.

Abstract: A computer system and a corresponding method perform a query to retrieve data from a database. The computer system comprises a Data-Base Management System (DBMS) with an optimizer. A Query Execution Plan (QEP) is generated for the query. The QEP is assessed by considering statistical values about previous executions of the query according to the QEP to decide whether to choose the QEP or to generate a new QEP. Furthermore, the statistical values on previous executions of the query are exploited during query optimization. The query is executed according to the chosen QEP. For optimizing the execution of future queries, statistical values about the execution of the query are collected during execution.