ALTERING DATA TYPE OF A COLUMN IN A DATABASE
    1.
    发明申请
    ALTERING DATA TYPE OF A COLUMN IN A DATABASE 审中-公开
    更改数据库中的列的数据类型

    公开(公告)号:US20160147776A1

    公开(公告)日:2016-05-26

    申请号:US14552902

    申请日:2014-11-25

    IPC分类号: G06F17/30

    摘要: Disclosed herein are system, method, and computer program product embodiments for altering the data type of a column in a database. An embodiment operates by converting an original dictionary associated with a column into a new dictionary. The new dictionary stores the values of the original dictionary using a different data type. An index vector containing the keys of the original dictionary is then updated to contain the associated keys of the new dictionary. Because the size of the original dictionary is often substantially smaller than the number of rows in the associated column, this dictionary conversion decreases the computation cost to the database system of altering the data type of the column and reduces or even minimizes database downtime for users.

    摘要翻译: 这里公开了用于改变数据库中的列的数据类型的系统,方法和计算机程序产品实施例。 实施例通过将与列相关联的原始字典转换为新字典来操作。 新字典使用不同的数据类型存储原始字典的值。 然后,将包含原始字典的键的索引向量更新为包含新字典的相关键。 由于原始字典的大小通常远小于相关列中的行数,因此该字典转换会降低数据库系统的更改列数据类型的计算成本,并减少或甚至最小化用户数据库停机时间。

    Efficient Database Undo / Redo Logging
    2.
    发明申请
    Efficient Database Undo / Redo Logging 有权
    高效数据库撤消/重做日志

    公开(公告)号:US20160147786A1

    公开(公告)日:2016-05-26

    申请号:US14553833

    申请日:2014-11-25

    IPC分类号: G06F17/30 G06F11/14

    摘要: Log records are accessed as part of a database operation in a database. The log records log insert, update, and delete operations in the database and include, for each row, a row position, a fragment identifier (ID), and a row ID. Thereafter, as part of the database operation, rows specified by the log records are located by: using the fragment identifier and the row position within the corresponding record of the log if the fragment with the corresponding fragment identifier is still available, otherwise, using the row identifier within the corresponding record of the log to look up the row position in an index of a corresponding row identifier column. The database operation is then finalized using the located rows. Related apparatus, systems, techniques and articles are also described.

    摘要翻译: 日志记录作为数据库中数据库操作的一部分进行访问。 日志记录数据库中的日志插入,更新和删除操作,并为每行包括行位置,片段标识符(ID)和行ID。 此后,作为数据库操作的一部分,由日志记录指定的行通过以下方式定位:如果具有相应分段标识符的片段仍然可用,则使用片段标识符和日志对应记录中的行位置,否则使用 日志的相应记录中的行标识符,以查找相应行标识符列的索引中的行位置。 然后使用定位的行完成数据库操作。 还描述了相关设备,系统,技术和物品。

    Method and system to avoid space bloating during run-time compression
    4.
    发明授权
    Method and system to avoid space bloating during run-time compression 有权
    方法和系统,以避免运行时压缩期间的空间膨胀

    公开(公告)号:US08965857B2

    公开(公告)日:2015-02-24

    申请号:US13730207

    申请日:2012-12-28

    IPC分类号: G06F7/00 G06F17/30

    CPC分类号: G06F17/30312

    摘要: Methods, systems, and computer program products are provided to manage a database system. The method includes locking during a database system idle time access by the database system to a data page of a data allocation unit, compressing during the database system idle time a data stored in the locked data page, and recording during the database system idle time an indication that the compressed and locked data page includes free storage space, wherein unlocked data pages of the data allocation unit are accessible by the database system during the compressing of the data stored in the locked data page. Thus, the data page may be compressed during idle time and the space freed therein may be used during a subsequent run time without the need for a reorganization of the data pages within the corresponding table (as in, for example, operation of a reorg+rebuild SQL command combination).

    摘要翻译: 提供方法,系统和计算机程序产品来管理数据库系统。 该方法包括在数据库系统空闲时间期间锁定数据库系统对数据分配单元的数据页的访问,在数据库系统空闲时间期间压缩存储在锁定数据页中的数据,以及在数据库系统空闲时间期间的记录 指示压缩和锁定的数据页面包括空闲存储空间,其中在压缩存储在锁定的数据页面中的数据期间,数据库系统可访问数据分配单元的解锁数据页。 因此,可以在空闲时间期间压缩数据页面,并且可以在随后的运行时间期间释放其中的空间,而不需要重新组织相应表格内的数据页面(例如,在例如reorg + 重建SQL命令组合)。