摘要:
Systems, methods, and products for database system transaction management are provided herein. One aspect provides for annotating via a computing device at least one data object residing on the computing device utilizing at least one transaction tag, the at least one transaction tag being configured to indicate a status of an associated data object; processing at least one database transaction utilizing a transactional memory process, wherein access to the at least one data object is determined based on the status of the at least one data object; and updating the status of the at least one data object responsive to an attempted access of the at least one data object by the at least one database transaction. Other embodiments and aspects are also described herein.
摘要:
Systems, methods, and products for database system transaction management are provided herein. One aspect provides for annotating via a computing device at least one data object residing on the computing device utilizing at least one transaction tag, the at least one transaction tag being configured to indicate a status of an associated data object; processing at least one database transaction utilizing a transactional memory process, wherein access to the at least one data object is determined based on the status of the at least one data object; and updating the status of the at least one data object responsive to an attempted access of the at least one data object by the at least one database transaction. Other embodiments and aspects are also described herein.
摘要:
A method, system and computer program product for improving performance of concurrent data inserting provide the features of adding a prefix to each key value in an index, wherein the prefix has a default value, allocating a corresponding prefix to each concurrent inserting process in response to an occurrence of a hot spot mode being detected, wherein each allocated prefix is different from the default value, performing an inserting operation in the hot spot mode, wherein the inserting operation includes deciding whether a key value can be inserted with the default value of the prefix, in response to a determination that an insertion of a key value with the default value of the prefix can be performed, inserting the key value with the default value of the prefix, and in response to a determination that an insertion of a key value with the default value of the prefix cannot be performed, inserting the key value with another prefix allocated by the inserting process.
摘要:
A system and method for concurrency control of hierarchically structured data is provided. Lock requests on a target node are processed by exploiting ancestor-descendant information encoded into prefix encoded node identifiers (IDs). A set of implicit locks on ancestor nodes along a path from an immediate parent of a target node to a root node is derived from an explicit lock request on a target node. A logical lock tree describing existing lock modes for ancestor nodes is consulted to determine compatibility with the derived set of implicit locks. If existing lock modes for ancestor nodes are compatible with the derived set of implicit locks, a lock request on a target node is granted. Otherwise, the lock request is denied. A lock release request follows the reverse process; a target node in a particular transaction is released, as are subsequent locks on its ancestors made by the same transaction.
摘要:
A partial index availability system places, in a restricted state, all pages in the index associated with a structure modification, when an error occurs in processing a log of the said structure modification. This maintains traversability of the rest of the index that is not in restricted state. The system locates and marks a left sentinel and a right sentinel associated with a non-leaf page that is in a restricted state preventing an undo of a transaction. The sentinels prevent a transaction from accessing an uncommitted change associated with the non-leaf page. After a recovery procedure is run the entire index is made available. During the period between the placement of the index pages in LPL or rebuild pending to the time of final removal of these pages from their restrictive states as a result of a recovery procedure being run, the users are given access to the non-restricted portion of the index.
摘要:
A new sub-document versioning method for record storages of XML documents which uses virtual cutting points to ensure that a search tree is able to support multiple versions of sub-documents and provide efficient mechanisms for XML updating. Record boundaries and virtual cut points divide the two-dimensional space, the horizontal axis representing node identifiers in document order and vertical axis representing version numbers, into rectangles. The bottom corner of the rectangle is used to represent the rectangles and the corresponding information of the corner is added to the search tree index.
摘要:
Castout processing for duplexed data structures. A selective data item is written from a primary instance of a data structure to at least one storage medium. A determination is made as to whether the selective data item can be deleted from a secondary instance of the data structure. If the selective data item can be deleted, it is deleted from the secondary instance.
摘要:
A method and apparatus for online reorganization of a database which does not prevent a process from accessing the database during the data reorganization. The invention uses a non-blocking drain to lock on a database, unloads a copy of the data contained in the database, reorganizes the copied data, loads the reorganized data into a shadow location, applies log records to the shadow location data so that the reorganized data may be adjusted for any changes to the database after the data was copied and reorganized, and then replaces the data in the database with the reorganized data. The non-blocking drain does not prevent other requests on the database from being processed while the reorganization lock is in place, except briefly when the reorganized data replaces the data in the database.
摘要:
A method and system for providing a scalable storage scheme for native hierarchically structured data of relational tables, includes a base table with indicator columns with information pertaining to hierarchically structured data of a document, data tables for storing the hierarchically structured data corresponding to the indicator columns, and node identifier indexes corresponding to the data tables for mapping between the indicator columns and the hierarchically structured data in the data tables. In an embodiment, actual data for each hierarchically structured data (such as XML) column is stored in a separate data table, and each data table has a separate node identifier index. The node identifier index is searched with a key containing the document identifier and a logical node identifier is used, and a record identifier of a record in the data table containing the node assigned the logical node identifier is retrieved.
摘要:
A method and system for formatting space in a storage device for a database system is disclosed. The method and system include formatting a first increment for creating a database file and asynchronously formatting at least one subsequent increment for the database file in a background of the database system.