Abstract: Managing different versions of a data record is provided. A mapping is maintained between a version-independent logical record identifier and a version-dependent physical record row identifier that correspond to each data record within a plurality of data records of a data table using a logical record identifier to physical record row identifier indirection mapping table. Entries within leaf pages of an index associated with the data table are updated to point to the version-independent logical record identifier corresponding to a data record instead of pointing to the version-dependent physical record row identifier corresponding to the data record. The logical record identifier to physical record row identifier indirection mapping table is updated in response to performing an operation on the data record instead of updating the entries within the leaf pages of the index associated with the data table.

Abstract: A method, information processing system, and computer program storage product optimize the placement of database objects on a multiplicity of storage devices. A set of database objects are placed on a first storage device in a multiplicity of storage devices. Each storage device comprises differing characteristics. A query workload is run on the set of database objects that have been placed on the first storage device. Profiling information associated with the query workload that is running is collected. A subset of database objects is selected from the set of the database objects to be stored on a second storage device. The second storage device is a separate physical device from, and performs faster than, the first storage device. The subset of database objects is stored on the second storage device and all remaining database objects in the set of database objects on the first storage device.

Abstract: Managing a multi-version data record database is provided. A mapping is maintained between a logical record identifier and committed and uncommitted physical record identifiers corresponding to data records using an indirection mapping table. Entries are updated within an index to point to the logical record identifier instead of the committed and uncommitted physical record identifiers. The committed physical record identifier corresponding to a data record is read from the indirection mapping table to access a committed version of the data record while a writer is modifying the data record to prevent the writer from blocking a reader. An uncommitted physical record identifier corresponding to the data record is written in the indirection mapping table to insert a new uncommitted version of the data record within a data table while the reader is reading the committed version of the particular data record to prevent the reader from blocking the writer.

Abstract: A system and method for adjusting space allocated for different page sizes on a recording medium includes dividing the recording medium into multiple blocks such that a block size of the multiple blocks supports a largest page size, and such that each of the multiple blocks is used for a single page size, and assigning an incoming page to a block based on a temperature of the incoming page.

Abstract: Staging data record changes from a faster storage medium to a slower storage medium using data query rewriting is provided. In response to receiving a data query corresponding to a particular data record, it is determined whether the data query is one of a transactional data query or an analytical data query. In response to determining that the data query is a transactional data query, the transactional data query is rewritten to apply transactional delta changes to the particular data record on a storage-class memory of a computer. In response to determining that the data query is an analytical data query, the analytical data query is rewritten to select and reconcile each data record corresponding to the particular data record stored on the storage-class memory with the particular data record stored on a persistent data storage device of the computer.

Abstract: Staging data record changes from a faster storage medium to a slower storage medium using data query rewriting is provided. In response to receiving a data query corresponding to a particular data record, it is determined whether the data query is one of a transactional data query or an analytical data query. In response to determining that the data query is a transactional data query, the transactional data query is rewritten to apply transactional delta changes to the particular data record on a storage-class memory of a computer. In response to determining that the data query is an analytical data query, the analytical data query is rewritten to select and reconcile each data record corresponding to the particular data record stored on the storage-class memory with the particular data record stored on a persistent data storage device of the computer.

Abstract: Managing a multi-version database is provided. A logical record identifier to physical record row identifier indirection mapping table on a solid-state storage device is extended to include a plurality of delta blocks. A delta block within the plurality of delta blocks is maintained for each primary key in a plurality of primary keys associated with a data table on a magnetic hard disk storage device.

Abstract: Managing a multi-version database is provided. A logical record identifier to physical record row identifier indirection mapping table on a solid-state storage device is extended to include a plurality of delta blocks. A delta block within the plurality of delta blocks is maintained for each primary key in a plurality of primary keys associated with a data table on a magnetic hard disk storage device.

Abstract: Managing different versions of a data record is provided. A mapping is maintained between a version-independent logical record identifier and a version-dependent physical record row identifier that correspond to each data record within a plurality of data records of a data table using a logical record identifier to physical record row identifier indirection mapping table. Entries within leaf pages of an index associated with the data table are updated to point to the version-independent logical record identifier corresponding to a data record instead of pointing to the version-dependent physical record row identifier corresponding to the data record. The logical record identifier to physical record row identifier indirection mapping table is updated in response to performing an operation on the data record instead of updating the entries within the leaf pages of the index associated with the data table.

Abstract: Large graph data in many application domains dynamically changes with vertices and edges inserted and deleted over time. The problem of identifying and maintaining densely connected regions in the graph thus becomes a challenge. Embodiments of the invention describe a method using a k-core measure as a metric of dense connectivity over large, partitioned graph data stored in multiple computing servers in a cluster. The method describes steps to identify a k-core subgraph in parallel and to maintain a k-core subgraph when a new edge is inserted or an existing edge is deleted. The embodiments thus enable practitioners to identify and monitor large scale graph data, such as exemplified by multiple topical communities in a social network, in a scalable and efficient manner.

Abstract: Managing different versions of a data record is provided. A mapping is maintained between a version-independent logical record identifier and a version-dependent physical record row identifier that correspond to each data record within a plurality of data records of a data table using a logical record identifier to physical record row identifier indirection mapping table. Entries within leaf pages of an index associated with the data table are updated to point to the version-independent logical record identifier corresponding to a data record instead of pointing to the version-dependent physical record row identifier corresponding to the data record. The logical record identifier to physical record row identifier indirection mapping table is updated in response to performing an operation on the data record instead of updating the entries within the leaf pages of the index associated with the data table.

Abstract: A system and method for managing a cache includes monitoring a temperature of regions on a secondary storage based on a cumulative cost to access pages from each region of the secondary storage. Similar temperature pages are grouped in logical blocks. Data is written to a cache in a logical block granularity by overwriting cooler blocks with hotter blocks.

Abstract: A system and method for managing a cache includes monitoring a temperature of regions on a secondary storage based on a cumulative cost to access pages from each region of the secondary storage. Similar temperature pages are grouped in logical blocks. Data is written to a cache in a logical block granularity by overwriting cooler blocks with hotter blocks.

Abstract: A method, information processing system, and computer program storage product optimize the placement of database objects on a multiplicity of storage devices. A set of database objects are placed on a first storage device in a multiplicity of storage devices. Each storage device comprises differing characteristics. A query workload is run on the set of database objects that have been placed on the first storage device. Profiling information associated with the query workload that is running is collected. A subset of database objects is selected from the set of the database objects to be stored on a second storage device. The second storage device is a separate physical device from, and performs faster than, the first storage device. The subset of database objects is stored on the second storage device and all remaining database objects in the set of database objects on the first storage device.