Hello Nandan Hegde and thank you for your question.
The External Data Source in Azure Data Warehouse appears to be only for data loading using Polybase, not other SQL databases.
However you can use
elastic query in your Azure SQL database to query the Azure data warehouse. This way the writing is done by your database, and you do not have to worry about giving write permissions.
In the Database,
create the credentials, then create the external data source:
CREATE EXTERNAL DATA SOURCE <data_source_name>
WITH
( LOCATION = '<remote_server_name>.database.windows.net'
, CREDENTIAL = <credential_name>
, TYPE = RDBMS
, DATABASE_NAME = '<database_name>' )
;
--https://docs.microsoft.com/en-us/sql/t-sql/statements/create-external-data-source-transact-sql?view=azuresqldb-current#overview-azure-sql-database
Then just
CREATE EXTERNAL TABLE <Table_name>
(
<Table_Schema>
)
WITH <data_source_name>
Please let me know if this helps.
Regards,
Martin
