Читать книгу Official Google Cloud Certified Professional Data Engineer Study Guide - Dan Sullivan - Страница 40

Semi-structured data, as noted earlier, does not follow a fixed tabular format and instead stores schema attributes along with the data. In the case of document databases, this allows developers to add attributes as needed without making changes to a fixed database schema. Two ways of storing semi-structured data are as documents or as wide columns. An important distinction between the two is how data is retrieved from them.