【Engingeering】Single Source of Truth

Posted by 西维蜀黍 on 2021-10-26, Last Modified on 2022-02-19

Single source of truth

Definition 1

In information systems design and theory, single source of truth (SSOT) is the practice of structuring information models and associated data schema such that every data element is mastered (or edited) in only one place. Any possible linkages to this data element (possibly in other areas of the relational schema or even in distant federated databases) are by reference only. Because all other locations of the data just refer back to the primary “source of truth” location, updates to the data element in the primary location propagate to the entire system without the possibility of a duplicate value somewhere being forgotten.

Deployment of an SSOT architecture is becoming increasingly important in enterprise settings where incorrectly linked duplicate or de-normalized data elements (a direct consequence of intentional or unintentional denormalization of any explicit data model) pose a risk for retrieval of outdated, and therefore incorrect, information. A common example would be the electronic health record, where it is imperative to accurately validate patient identity against a single referential repository, which serves as the SSOT. Duplicate representations of data within the enterprise would be implemented by the use of pointers rather than duplicate database tables, rows, or cells. This ensures that data updates to elements in the authoritative location are comprehensively distributed to all federated database constituencies in the larger overall enterprise architecture.

Definition 2

Data exists in various systems across an organization. When these systems exist in silos it poses a challenge for businesses looking to make data-driven decisions, as not all members of the organization are operating off of the same data. Modern businesses are now moving toward a single source of truth model to overcome this challenge.

A single source of truth (SSOT) is the practice of aggregating the data from many systems within an organization to a single location. A SSOT is not a system, tool, or strategy, but rather a state of being for a company’s data in that it can all be found via a single reference point.

A simple example of this is search engines. Let’s say a searcher enters a query about their favorite restaurant. Google aims to be the single source of truth for anything they may need to know about this restaurant; such as, the restaurant’s hours, phone number, local locations, menu link, ratings, and popular times. Google is bringing data from many sources (Google maps, the restaurant’s website, Yelp or Google ratings, etc.) to be the searcher’s single source of truth for the data they may want to know about that restaurant.