Explanation:
Graphical user interface, text, application, email Description automatically generated

Step 1: Create an external data source
You can create external tables in Synapse SQL pools via the following steps:
* CREATE EXTERNAL DATA SOURCE to reference an external Azure storage and specify the credential that should be used to access the storage.
* CREATE EXTERNAL FILE FORMAT to describe format of CSV or Parquet files.
* CREATE EXTERNAL TABLE on top of the files placed on the data source with the same file format.
Step 2: Create an external file format object
Creating an external file format is a prerequisite for creating an external table.
Step 3: Create an external table
Reference:
https://docs.microsoft.com/en-us/azure/synapse-analytics/sql/develop-tables-external-tables