Which command in Azure Synapse Analytics allows querying external data, including analytical stores?

OPENROWSET is the command in Azure Synapse Analytics that allows you to query external data directly from a query, including data stored in analytical stores. It provides the capability to access data residing in different data sources, whether it's structured or semi-structured. This command can be particularly useful for integrating data from external systems or when wanting to perform ad hoc queries on the outside datasets without first having to create a specific linked server or external table.

Furthermore, OPENROWSET supports querying data in formats such as CSV, Parquet, or JSON, making it highly versatile for various analytical needs across diverse data formats. This capability enables data engineers to efficiently work with large datasets residing outside the primary database, facilitating the integration and analysis of data across multiple sources.

In contrast, the other choices do not serve the same role. SELECT is used to retrieve data from tables and views within the same database environment, while OPENQUERY is specifically tied to linked servers and is designed to run a pass-through query on that linked server. IMPORTDATA is not a recognized command in this context, making it an unsuitable choice.