external-table-function.md

title	description	ms.reviewer	ms.topic	ms.date
external_table()	Learn how to use the external_table() function to reference an external table by name.	alexans	reference	03/02/2023

external_table()

References an external table by name.

Note

The external_table function has similar restrictions as the table function. Standard query limits apply to external table queries as well.

Syntax

external_table( TableName [, MappingName ] )

[!INCLUDE syntax-conventions-note]

Parameters

Name	Type	Required	Description
TableName	string	✔️	The name of the external table being queried. Must reference an external table of kind blob, adl, or sql.
MappingName	string		A name of a mapping object that maps fields in the external data shards to columns output.

Authentication and authorization

The authentication method to access an external table is based on the connection string provided during its creation, and the permissions required to access the table vary depending on the authentication method. For more information, see Azure Storage external table or SQL Server external table.

Related content

• External tables overview
• Create and alter Azure Storage external tables
• Create and alter SQL Server external tables.