Which file type can contain information for connecting to an external data source such as an SQL Server database?

The file type that can contain information for connecting to an external data source such as an SQL Server database is a .tds file. This file format stands for Tableau Data Source and is specifically designed for Tableau. A .tds file stores metadata, including the connection information needed to access the database, dimension definitions, and measures, as well as any calculations or formatting applied to the data within Tableau.

Using a .tds file simplifies the process of connecting to a data source, allowing users to share the connection details and predefined structure of the data model without exposing the raw data itself. It facilitates easier collaboration among Tableau users, as data can be consistently connected and utilized by different users in similar ways.

The other file types mentioned do not serve this purpose; for instance, a .csv file is a plain text file used for storing tabular data, a .json file is typically used for structured data interchange but does not store connection information, and a .mdb file is associated with Microsoft Access databases rather than Tableau's connection protocols.