The Experts below are selected from a list of 6 Experts worldwide ranked by ideXlab platform
Randall Weis - One of the best experts on this subject based on the ideXlab platform.
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The Origins of Asserted Versioning: IT Best Practices
Managing Time in Relational Databases, 2010Co-Authors: Tom Johnston, Randall WeisAbstract:This chapter discusses the origins of Asserted Versioning in IT best practices, specifically those related to versioning. Versioning is the IT community's way of providing queryable access to historical, current, and future data. It is believed that these practices are variations on four basic methods of versioning data. Those four types are: (i) Basic versioning; (ii) Logical delete versioning; (iii) Temporal gap versioning; and (iv) Effective time versioning. The simplest versioning method, called basic versioning, is to add a date to the primary key of the Table to be versioned, thus transforming it from a nontemporal into a Unitemporal Table, i.e. into a Table with one temporal dimension. In the logical delete versioning, a logical delete flag is included in the version Table. It has two values, one marking the row as not being a delete, and the other marking the row as being a delete. Effective time versioning is the most advanced best practice for managing versioned data in the IT world. Effective time versioning actually supports a limited kind of bitemporality. The chapter discusses each of these methods by means of examples, which include sample Tables and a running commentary on how inserts, updates, and deletes affect the data in those Tables.
Tom Johnston - One of the best experts on this subject based on the ideXlab platform.
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The Origins of Asserted Versioning: IT Best Practices
Managing Time in Relational Databases, 2010Co-Authors: Tom Johnston, Randall WeisAbstract:This chapter discusses the origins of Asserted Versioning in IT best practices, specifically those related to versioning. Versioning is the IT community's way of providing queryable access to historical, current, and future data. It is believed that these practices are variations on four basic methods of versioning data. Those four types are: (i) Basic versioning; (ii) Logical delete versioning; (iii) Temporal gap versioning; and (iv) Effective time versioning. The simplest versioning method, called basic versioning, is to add a date to the primary key of the Table to be versioned, thus transforming it from a nontemporal into a Unitemporal Table, i.e. into a Table with one temporal dimension. In the logical delete versioning, a logical delete flag is included in the version Table. It has two values, one marking the row as not being a delete, and the other marking the row as being a delete. Effective time versioning is the most advanced best practice for managing versioned data in the IT world. Effective time versioning actually supports a limited kind of bitemporality. The chapter discusses each of these methods by means of examples, which include sample Tables and a running commentary on how inserts, updates, and deletes affect the data in those Tables.
