> For the complete documentation index, see [llms.txt](https://docs.fabricplan.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fabricplan.com/documentation/readme/powertable-sheets/how-tos/adding-columns-overview/add-visual-column/relation-column.md). # Relation Column A relation column creates a one-to-many relationship between records in two tables. It links a record in a parent (master) table to one or more related records in a child (detail) table, enabling you to organize and manage related data across tables. This is called a **master-detail relationship**. This type of relationship is commonly used to model hierarchical data, such as customers and their orders, projects and their tasks, or departments and their employees. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.fabricplan.com/documentation/readme/powertable-sheets/how-tos/adding-columns-overview/add-visual-column/relation-column.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.