Unable to setup Function App to establish SQL connection

Requirement is to automate synchronization of iMIS business objects to SQL Server tables using an Azure Function so that updates occur nightly without manual intervention.

For this, we created Function App in Azure with pay-as-you-go subscription and .Net runtime stack and then enabled system assigned managed identity to it. We also granted Function App access to access SQL and its been added to sql db group as well and allowed access in firewall that all services/ resources to access server. In azure, we are using Create funnction is portal using azure template, and used Timer Trigger for this. We are running simple code in timer trigger to check if function app is able to connect to SQL database and that connection is established successfully, but keep getting following error :

2025-01-10T19:23:58Z [Information] Executing 'Functions.TimerTrigger1' (Reason='This function was programmatically called via the host APIs.', Id=e10df4da-93b0-4d16-a7a2-7800801ab32d)

2025-01-10T19:23:58Z [Error] Function compilation error

2025-01-10T19:23:58Z [Error] run.csx(2,17): error CS0234: The type or namespace name 'Data' does not exist in the namespace 'Microsoft' (are you missing an assembly reference?)

2025-01-10T19:23:58Z [Error] run.csx(3,7): error CS0246: The type or namespace name 'Azure' could not be found (are you missing a using directive or an assembly reference?)

2025-01-10T19:23:58Z [Error] run.csx(20,34): error CS0246: The type or namespace name 'SqlConnection' could not be found (are you missing a using directive or an assembly reference?)

2025-01-10T19:23:58Z [Error] Executed 'Functions.TimerTrigger1' (Failed, Id=e10df4da-93b0-4d16-a7a2-7800801ab32d, Duration=8ms)

We have installed package Microsoft.Data.SqlClient in Developer tools, but still this error is not getting resolved and as a result of which i am not able to test connection from function app to sql. Following code gives above error :

using System;

using Microsoft.Data.SqlClient;

using Azure.Identity;

using Microsoft.Azure.WebJobs;

using Microsoft.Extensions.Logging;

public static class Function

{

[FunctionName("TestSqlConnectionFunction")]

public static void Run([TimerTrigger("0 */5 * * * *")] TimerInfo myTimer, ILogger log)

{

    log.LogInformation($"C# Timer trigger function executed at: {DateTime.Now}");



    // Connection string with your provided details

    string connectionString = "Server=tcp:ciccccicimis.database.windows.net,1433;Database=iMIS-PROD-Archive;";



    try

    {

        // Create a new SqlConnection object with the connection string

        var connection = new SqlConnection(connectionString);



        // Open the connection to the database

        connection.Open();

        log.LogInformation("SQL Connection successful!");



        // Close the connection

        connection.Close();

    }

    catch (Exception ex)

    {

        // Log any errors

        log.LogError($"Error: {ex.Message}");

    }

}

}

cant use visual studio or cli or other azure cli editor because license isn't there. this needs to run in Azure portal, azure function app itself