engleză
Bitemporal data is coming, and major database management systems are beginning to support it. You need to know what is going on "under the hood" and this book that will make you the expert on bitemporal data that every IT organization should have on its staff. There's a lot more to bitemporal data than adding a second timestamp to history tables: for example, a temporal update of a single customer in a bitemporal customer table could require up to a dozen physical SQL transactions to complete. Vendors will eventually make it possible to write bitemporal transactions and bitemporal queries, without having to tell the DBMS how to carry them out. Bitemporal Data will qualify you to compare and contrast the bitemporal offerings from DBMS vendors. * Includes vendor-neutral explanations of bitemporal concepts and bitemporal functionality, and an unbiased review of the bitemporal offerings from the major DBMS vendors * Clarifies business user requests for temporal data by understanding what information bitemporal data provides that other kinds of data - such as data in non-temporal tables, history tables, data warehouses, or fact-dimension databases - do not provide * Explains the substantial increase in complexity between as-written temporal transactions and temporal queries, and the physical SQL activity required to carry out those temporal commands
